So You Want To Go Solar…

A few people – friends, friends of friends, complete strangers – have asked me what the best solar system to buy is. “How many solar panels?” or “Should I get a battery?” and “What is that thing growing out of your head?”.

To them I say:

Note: that totally isn’t me. Nor am I associated with (c) Snorg. But its funny, so click on it.

Everybody’s house is a little different. Everybody’s use case is a bit different. Solar isn’t just a cookie cutter approach; at least, not yet.

What I can say is that there are a few steps I’d recommend to anyone thinking about installing solar panels and/or a battery.

(Oh wait: I forgot the paragraph wailing about how slack I’ve been on the blog. That was it – well except to say I got a new job in November 2017 working in energy which is pretty rad, but keeps me way busy).

Motivation For Solar

People want solar for different reasons, and from my experience of the last two years, it breaks down into a few things.

Driving down electricity bills is usually numero uno, and there is nothing wrong with that. Investing thousands into something functional like a solar PV system, you’d want to see some payback and/or stick it to “The Man” if you’re angry about whatever it is “The Man” has done.

Green feelgood is another factor. Reducing your grid needs helps save operating costs on your house, as well as your carbon footprint. You also get to understand your ability to contribute to the energy ecosystem via renewable energy.

Curiosity is a relatively new thing, particularly for modern systems with API-driven inverters. Some people (me) like to watch what is happening on their solar system at various intervals, e.g.

After that, its a question of “Do you really *need* solar?”

Where To Start

First place is your electricity bill.

Look at the amount you consume on a daily basis across the year. Figure out whether there are major differences between summer, autumn, spring, and winter, and I’ll bet you start to see where the pain points are in terms of running certain devices in summer (AC) or winter (heating).

As I’ve said before: most of us get our bill, have a bit of a rage about it, and then pay it and move on. You need to take the time to analyse who you are, and what you use. It will be very helpful.

Have you spoken to your electricity provider about getting the best deal? Sometimes we pay too much via “lazy tax” where we can’t be bothered even making a phone call.

Have you told your electricity provider that you’re speaking to other electricity providers about the best deal? That can be quite the motivator.

Does your electricity provider offer “green” power options? That might elevate your bill slightly, but give you part of that feelgood factor you’re after.

Efficiency, Efficiency, Efficiency!

Next, I’m going to ask whether you’re doing everything you can to reduce your electricity consumption.

Energy Efficiency is a very much overlooked part of housing, particularly in warmer places like Australia. Building standards here aren’t so great compared to other parts of the world, and we compensate using air conditioners.

I have to say I’m guilty here of jumping into solar + storage before really checking why my bills were so high. The good news is, I’m addressing these issues now by getting awnings on my west-facing windows as well as installing downlight covers in the ceiling to reduce insulation gaps.

Perhaps it is something as simple as setting your thermostat too hot/cold, and trading money for a tiny bit of discomfort. In modern HVAC (Heating, Ventilation, Air Conditioning), each degree you set your AC up or down from 25oC can cost 10% more energy. Not cool. Or hot. Whatever.

Check all the gaps around your doors and windows. Deploy window coverings against the sun, or heavy curtains against the cold, wherever possible. Turn off the beer fridge if you’re not really using it. When you replace a device, look at the energy efficiency rating system (it can save you hundreds).

The possibilities are not endless, but they’re available, and significant.

The goal is to consume the minimum amount possible without making yourself too uncomfortable. And maybe a little discomfort isn’t such a bad thing 😉

Alright, so let’s say you’ve covered the energy efficiency thing, and have a fair handle on your bills. That’s half the battle. Let’s talk about solar.

CAN YOU HANDLE THE SOLAR?

Not every roof can handle a solar PV setup. I’ve lived in a house that could not, due to a lack of appropriate space.

Start by looking at your roof space on Google Maps, and see if you have north- or west-facing roof space that might host a decent array of panels, if you’re in in the Southern Hemisphere.  For those north of the equator, its south- or west-facing, obviously.

In some cases you might even want to have east-facing panels as well, due to your usage patterns. Morning people; they exist.

The more complex your roof layout, the more it is likely to cost for installation. Two storey installs can cost more in some cases. Single storey might get tricky if you’ve got multiple roof lines with minimal contiguous area.

Roofing material may also determine how difficult the install becomes, as different fixings and sealing methods are required.

If in any doubt, talk to a local installer. That’s where Google Reviews and recommendations can come in handy – find the right team and you’ll reap the benefits.

A Galaxy Of Solar Systems

The trouble with me recommending anything is that the internet will immediately have an opinion on it. You will read reviews that are negative about perfectly good solar PV equipment, maybe because an individual had a bad experience.

There are thousands of combinations of solar panels, inverters, and (if you require it) storage systems from which to choose. You’ve also got different metering options, which can affect how you get billed, and how you might leverage peak/offpeak power rates.

“How many panels do I get?” is a pertinent question, and my response is always that panels are cheap, so get as many as you can afford.

Remembering that in most new setups, you’re in a “net” situation i.e. the panels feed your house first, then sell any leftover energy back to the grid at a modest rate.

Trying to self-consume every last kWh you produce is a waste of time for a grid-connected system, in my opinion. You’ll end up with a smallish system that meets your needs generally, but you’ll miss a lot of the cost offset you get from feed in tariffs, and payback time will be no different, or longer.

Panels are cheap. Get as many as you can afford.

At the same time, get an inverter that will handle that load. Having 6kW of panels isn’t going to mean much if your inverter is designed for half that. I’ve got 6.5kW of panels and my inverter maxes out at 5kW, which is generally OK, but I’d like a bit more 😉

In Australia, I’d recommend a minimum of 5kW of panels. A system of that type will cost you around $6000-$7000 in Australia (installed). In the USA, Trumplandian authorities will ensure it continues to be about double that.

Adding A Battery

Adding storage can double (or more) the cost of a system pretty quickly.

At this point (February 2018) it will extend the payback time accordingly because lithium batteries are still coming out of the early adopter phase. It becomes a question of capital investment versus operating cost.

If you get only the solar panels, you can get payback in under 6 years.

This makes the assumption that you’re operating the system with a decent amount of thought. Move heavy loads to the middle of the day when the sun is shining and the panels are blazing. Make the most of your feed-in-tariffs, where available. Be aware of your efficiency issues, and address them.

If you do all this right, you could get payback down below 5 years, BUT you’ll still be paying an electricity bill, even if its smaller now.

Today, the battery option will take your payback up past 6 years again, and maybe as high as 8 depending on the specifics.

There is a benefit, though: your operating costs for electricity will be closer to zero than if you have solar alone. Heck, maybe you might even turn a small profit!

There are additional benefits to your battery install as well, if you have smart technology like Reposit Power attached to the system. Selling power for $1 / kWh a few times a year might not sound like much, but when your total bill is close to zero, its heading toward profit.

It can help you save money on electricity via arbitrage if you have the right metering setup. Reposit maintain a list of good installers to use in Australia, who will ensure you get the best result.

But How Much Will I Save???

Well, I can’t really answer that, unequivocally. A lot depends on individual circumstances.

I’m saving about $2000 per year over the first two years, having made small changes to how I run my house. I continue to make these changes as I explore ways to reduce my usage.

If you’re just going to whack the system in for something cool to look at, but not change any of your habits, expect your savings to match your behaviour.

P.S. if you want to move providers, and grab a $35 credit while getting a 12c feed-in-tariff, hit me up on Twitter for my Diamond Energy account number. They’re green, clean, and lean, as well as being partnered with Reposit for Grid Credits.

Will the Grid go into a Death Spiral?

You’ve probably heard the term “Death Spiral” applied to many things. Insurance. Economics. Obamacare. TV (or Presidential) Ratings. Whatever.

Recently there was an article quoted by the smartest Wind Turbine in Australia, as seen on Twitter:

I replied, somewhat off-the-cuff, that the “death spiral” was a bit of a furphy, and was subsequently challenged to a blog post about it.

I’ll give it my best shot – but strictly in layman’s terms, and mainly with a view of the Australian market. Apply the lessons where you will.

WestERN Australia Grid Primer

Western Australia, in terms of land area, is big. I’m talking Texas-plus-Alaska big, for those of you playing in the US of A.

While it has a lot of land, it has less than 3 million people. That means a relatively small market for energy provision. They have a local grid (SWIS*) in the heavily populated south west around Perth (pop 1.95M), one of the most isolated cities on Earth.

* South West Interconnected System

The SWIS covers the SW corner of the state, and is serviced by Synergy. That’s right – there is only one electricity company, and its government owned. But you get your choice of two gas companies!

Death Spiral
The gas is also cursed…

Outside of the SWIS, everything else is the responsibility of Horizon Power. That is a big area to manage, and big means expensive.

Large towns (by Australian standards) can be hundreds of kilometres apart, mostly on the isolated coastline facing the Indian Ocean. Inland towns might only exist for mine operations, or reside on historical roads that still provide services for farming or Aboriginal communities.

One bushfire out there, or a car accident into the wrong pole, can cut what constitutes a grid connection in an instant.

A lot of the electricity outside the SWIS is also heavily subsidised. Some communities get diesel shipped in for generators to run in parallel with renewables. Cost price to do so is 60c/kWh once logistics is factored in, and would be unfair to ask consumers to stump up for all of it.

But governments are only able to bear these costs for so long.

WA Government Budget Repair

As another article says,  the WA Government is increasing power prices in order to undertake budget repair. This includes an electricity price increase for consumption per kWh, as well as fixed charges.

The daily charge residents must pay to be connected to the grid will almost double, resulting in a 10.9 per cent rise on the cost from last year.

Of course, being politicians, they’ve blamed the previous government (now the opposition) for “the mess” inherited. Proving the age-old idiom: Politicians can be raving douchecopters.

Prices are also going up in WA on things like public transport, water, sewerage, and other things like port fees.

Consumers never like increases. Particularly in their electricity bill, and especially in the fixed charges.

You can try to make your household import less energy, but its not going to help a set daily fee get any lower. In fact the data shows that energy usage has stopped increasing in recent years in the NEM on the Eastern seaboard.

In some parts of WA, outside the SWIS, they have a cap on solar installations, to prevent network fluctuations. Seems weird that, in one of the sunniest places on earth, they’d stop installing solar panels, right?

Energy stability is key, particularly in a far-flung network like WA. Its interesting to note that Horizon are undertaking trials to regulate solar power flow in the Gascoyne region shortly (there’s that windmill again).

WA is a state with a lot of sun, potential for a lot of wind, but has challenges bringing it to bear in a safe and reliable manner.

The cap on solar installs is something I’m going to address from a market standpoint, in an upcoming post about my time at Renewable Cities Forum in June.

Putting The Article Into Context

The original article quotes Dr Jemma Green of Power Ledger, a company involved in blockchain retail of renewable energy.

“The perverse outcome of increasing the fixed supply charge is that in the short-run you might get more money, but in the longer run you’re going to push people off the network and look for more cheaper alternatives,” she said.

This is a stark warning to electricity generators and retailers. Particularly in the Australian market where prices have risen more than 60% on average in the last decade.

And while Dr Green believes it is a fair way to help the economic state of WA – as a short-term solution – solar households (25% of the state) in particular would feel somewhat resentful.

The point about being a short term fix is important. Governments simply can’t keep forcing consumers to pay more, particularly while solar and storage systems get cheaper.

Would this move by the Government of WA motivate people to leave? Dr Green says:

“… taken to the extreme means the network is no longer getting the revenue needed to support itself and it creates a death spiral.”

A government, or market operator, would be supremely ignorant (or greedy) to miss the warning signs of such a crisis. She has said “extreme” after all.

That is Reason #1 a death spiral is unlikely: despite what we think, the top end of town are not so stupid (or greedy) as to eat their own tail.

Anatomy Of A Death Spiral

To make something spiral (up or down), you’ve got to have some fairly consistent motivating factors. These factors may be constant, or under acceleration.

We certainly have consistent price rises, here in Australia. New South Wales customers are looking at price rises of up to 16% as of this month, as one example.

The quoted figure over the last decade is a jump of prices in the order of 60-100%, partly due to increased network connection costs.

At the same time, we’ve got larger energy providers like Energy Australia posting profits in the tens of millions. So there is a bit of fat to be trimmed there, if needs be.

But will it force customers to leave the grid?

That is probably the wrong question. A more pointed one is: can customers afford to leave the grid?

Certainly not for today’s prices on storage. If you went out and bought a Powerwall 2, and a solar PV system on the larger side (6kW+), you’re looking at about $16K. The number of households who can afford that is in the minority.

Even then, with only 13kWh of storage, the average household won’t make it through a 48 hour period without sunlight. WA gets clouds, too.

Most off-grid types recommend a minimum of 4 days’ storage, plus a generator for emergencies. Now you’re talking about upwards of $30k, because most people don’t fancy sitting in the dark.

Reason #2 the grid won’t death spiral: in the near future, consumers can’t afford to leave en masse. Therefore the network charges, and consumption fees, are still going to keep the grid afloat.

Pardon My French

Plus ça change, plus c’est la même chose

 – Jean-Baptiste Alphonse Karr

Don’t worry, that will make sense in a minute.

As the landscape changes in our energy network, newer technologies are emerging, and disrupting, the status quo.

repositpower

Reposit Power are one of the companies at the forefront of changing this landscape. The concept of Virtual Power Plants is the here and now, and Reposit, along with other companies, want to make it available to everyone.

At Energy Networks Australia last year, and again at Renewable Cities this year, you could see the shift in thinking.

The analysts are vocal because they’re trying to get people to listen. The see a bright future and a market of endless technological possibilities.

The salesman are animated, because they’re trying to set up a market. They see great opportunities to put their products into action, and get that market share.

The industry, both generating and retailing, are a equal parts bemused, scared, and curious.

As we see battery uptake increase across Australia, a lot of these technologies are going to change the market place. Horizon Power are trialing control of domestic solar PV output.

How much easier would that be with a grid scale battery in front? Networks could start doing their own frequency regulation and dispatch, with strategically-placed storage (battery, pumped hydro, train full of rocks, whatever).

They could limit long-term infrastructure spend by tapping user storage in times of need, and at a lower price than it costs to run traditional or renewable generation. And you don’t have to transmit it over kilometres; its right there in the neighbourhood!

If you’re a consumer in 2020, how mad would you be to disconnect from the grid, when you can contribute, and profit, from it?

As old mate Jean-Baptiste said above: the more things change, the more they stay the same. Staying connected to the grid will be as normal tomorrow, as it was yesterday.

Reason #3 the death spiral won’t happen: consumers will eventually become participants.

Rumours Of My Death Spiral Have Been Greatly Exaggerated

Prices go up. That’s capitalism.

Anyone reading this article who isn’t on board with the solar + storage thing is going to accuse me of being a rich man. Of leaving the poor people behind, and forcing those left on the grid full-time to pick up the tab.

And that is certainly a risk that the WA Council of Social Services highlighted when the government announced these price rises. Those who are already struggling to pay the bills are going to be hit hardest.

Of course, it would be nice if prices didn’t go up quite so much as 10-16% in one year. But you can’t blame renewables for that – or you can, but you’ll look like an idiot.

If you want to blame someone, point your finger at the Federal Government’s appalling lack of energy policy.

Death Spiral
Not pictured: coherent, forward-looking energy policy (c) abc.net.au

Look at the State Governments and their mates in the energy industries, lobbying for bigger, gold-plated networks we don’t need.

Now think about the private players who are entering the market. They’re seeking profits, sure, but they’re bringing technology and ideas designed to minimise spending, while maximising value. They’re not interested in a death spiral.

Renewable energy without subsidies is now beating fossil fuels. Distributed microgrids are cheaper (and quicker) to build, and easier to maintain than massive, centralised networks. Even companies like Horizon Power know that, and are putting it into practice.

I don’t think we’re going to see the grid die. I think we’re going to see it grow into something more secure, resilient, and flexible. And the longer term costs of running it will decrease per capita.

The grid will still be there for us, and we’ll be there for the grid. It might get a bit bumpy, so keep your limbs inside the ride at all times.

SolarEdge Updates

I’ve been a bit busy to monitor my usage regularly, of late. Feeling out of touch, I made a point of checking my solar generation after recent rainy weeks.

It seemed a little low. Usually I hit 5kW around the middle of the day, but was peaking out at 4.6kW. I was contacted by someone who lives nearby with a corresponding fall in numbers.

The only theory we have to go off is lower angle of the sun. Additionally, because there were two weeks of Autumn where we almost never saw direct sunlight, we didn’t see the slow decline over time.

Its like seeing someone’s kids only occasionally – can’t believe how much they’ve grown! Their parents see it every day.

SolarEdge Updates

Having not checked anything for a while, I headed over to the SolarEdge Monitoring Portal to compare their results to Reposit. Having a second source for comparison is very helpful to sort out any discrepancies.

Well, there certainly have been some changes! And all of them look like winners.

The first noticeable change was the new Monthly profile for Power and Energy.

SolarEdge Updates
April 2017 to date

There was a period where the “self-consumption” figure wasn’t being reported through some conflict with the Reposit interface. That’s back, which is great.

Added to this is the “From Battery” stat which is quite cool. It features both in the Consumption summary figure, and the bar graph. This is only recent, so I look forward to that percentage figure “from batteries” smoothing out with a larger data sample.

If you mouse-over any of those bar graphs it gives you the details, in kWh, for the days that have been completed. Again – very vool.

I also hadn’t given much thought to the year-on-year comparison before I had enough data. Now its very handy to answer questions I and my near-neighbour have about long-term performance.

SolarEdge Updates 2

For reference, the figures are in the table below for the three months with suitable data.

Month MWh 2016 MWh 2017
February 0.728 0.780
March 0.695 0.617
April 0.523 0.588*

* As of April 24.

What I find really interesting is the March figure; despite having an extra 1.5kW of panels this March compared to 2016, the weather meant I didn’t generate quite as much.

Moving forward, I’m sure subsequent years and months will prove to be most interesting. I love me some data!

Live Baby Live!

They’ve also updated the Overview panel to have near-real-time feeds of consumption. I did a quick screen cap of this and stuck it on my YouTube Channel. I like.

All in all, a great round of SolarEdge Updates as we move toward the cooler months.

 

Reducing Climate Change Risks

This is my entry to the Masdar 2017 Engage Global Social Media Competition. The aim is to describe which technology will help reduce climate change, and why.

As scientific bodies continue to explore and model the effects of climate change, the technologists, disruptors, and entrepreneurs are seeking ways to combat it. The use of renewable power in the form of wind and solar is one of the key areas.

 

However, a valid criticism of renewable energy is stability: if the sun doesn’t shine, and the wind doesn’t blow, solar and wind are in under-supply. If the sun DOES shine brightly and the wind picks up, the renewable energy grid produces oversupply.

This situation is prominent in the California “Duck Curve”. The belly of the duck is over-generation from solar, while the head of the duck is the consumption ramp for night-time domestic use.

California Duck Curve showing oversupply / ramp requirement paradox (c) GTM

As domestic and commercial solar uptake increases across the world, there is a genuine risk to existing grids. Trying to address this issue alongside a mix of traditional power generation is difficult. Large, traditional generators cannot uplift generation, or halt it, at short notice.

I believe the natural solution is widespread adoption of storage technology.

Domestic storage will mature rapidly over the next 5 years, as household battery options become cheaper, due to vertical integration of the production process. This will be particularly true in established Western housing markets, particularly those dwellings with rooftop solar options.

It also enables the concept of virtual power plants for retailers to access power stored in domestic appliances. In the future, consumers will engage in peer-to-peer trading via blockchain and other smart technologies. The net result is to lower the need for a traditional “grid” and the associated maintenance for poles and wires.

Industrial storage will see positive disruption to hi-tech engineering solutions, using renewable generation. Efficiency has a large role to play here, as innovation across multiple sectors leads to better production engineering.

The volatility of frequency required for running many heavy industries can be offset with larger scale storage. These battery systems act like a buffer, or regulator, in order to provide assurance of stability. Large storage can also be deployed by energy networks in order to back up local power infrastructure.

Transport storage is a key area for addressing carbon emissions. While cars are the major playground for this technology right now, the move to heavy transport, agriculture, and public transport offers a range of other benefits.

I call it “Transport storage” because it offers more than just a way to move people or goods from one place to another. There is the opportunity to place domestic, industrial, and transport storage in synch, to produce a more efficient outcome for renewable energy.

Consider the California Duck Curve I mentioned before. This is the result of “too much of a good thing” when we have an over-abundance of solar PV! What if there was a way to mitigate this?

The average shopping mall in most countries has a roof space in the hundreds of square metres. They also contain hundreds, if not thousands, of car spaces.

If we add solar panels on that roof space, and storage in the basement, we can effectively create a curve smoothing apparatus by plugging in a suitable number of EVs during daylight hours. A similar system could be used by places of work for the benefit of employees.

Such a system would draw not only from the local (mall rooftop) power, but also spill excess renewable energy into recharging the transport network in other places. This might take the form of powering connected public transport – like electric buses or trains – on site, or via the grid.

All the while, this large-scale storage and renewable generation helps flatten the belly of the duck during the day. When people return to their homes at night, they can cut the head off the duck using their domestic storage.

Storage, along with the associated smart management technologies, provides the cornerstone for a renewable energy future. The combination of increased efficiency, and reduction of fossil fuel burning, is undeniable.

Springtime for Positive Billing

As per my tweet earlier in the month, the new bill came in, and it is really  the definition of positive billing.

It is the first bill I’ve received with TOU (Time Of Use) tariffs, which changes the landscape a bit for me.

I already have data from Reposit Power about billing estimates on a daily basis. While they’re pretty sharp, the guys doing the billing are where it counts. I wanted to see how close all the estimates – including my own – would be to the truth.

The net result is a deposit into my bank account (yesterday) of $50.25.

Positive Billing Spring
Billing Summary November 2016

The Breakdown

The fixed costs were as follows, excluding GST, for the 84-day period.

Item Quantity Price Amount
Service connection fee 84 days 98.90 c/day $83.08

Usage over the period at the various TOU rates came to the following (all amounts are excluding GST).

Item Qty (kWh) Price (c/kWh) Amount
Peak – Rate 1* 24.962 30.5300 $ 7.62
Peak – Balance 0.000 31.4900 $ 0.00
Shoulder Rate 76.635 24.9700 $19.14
Off Peak 74.584 13.8400 $10.32

* This covers the first 340kWh / month

I imported only 176.181kWh over an 84-day period. That works out to just under 2.1kWh per day during that time. Only 0.3kWh in peak tariff period!

There were a couple of rainy days in a row that I recall. One of those coincided with hosting a family event, using the oven, and dishwasher a couple of times. As it was the weekend, shoulder rate tariff applied.

Factors in my favour are summarised in the table below.

Item Qty Price Amount
Net feed-in tariff -1099.299 kWh 8 c/kWh -$87.94
GridCredits -5.04 kWh 100 c/kWh -$ 5.04
Renewable Reward 84 days -8.710 c/day -$ 7.32
Direct Debit Discount 3.0 % -$ 3.60
Pay on Time Discount* 7.0 % -$ 6.75
Diamond Referral  2 -$35.00 -$70.00

* This amount is calculated against the previous bill

The export figure is massive at nearly 13.1 kWh per day! Its worth noting that the new panels I got in October covered about 25 of the 84 days in this billing cycle.

The first lot of GridCredits were applied to this bill, and that $5.04 is handy for knocking the top off that peak tariff.

Once you throw everything into a pile, and calculate GST, you get the balance of -$50.25. Diamond will credit your account for any amount of $50 or more owed. For the first time ever I have positive billing for electricity in my favour!

About those referrals…

Yes, Diamond have a pretty generous referral scheme. Both the existing customer and new customer get a $35 credit which is pretty sweet. Long may it continue!

Having just one of those per quarter could help the electricity bill head drastically toward zero. The question is, how many friends and family can you tap into on a regular basis? 🙂

Let’s remove that $70 amount from the equation to look at the regular money.

Just The Facts, Ma’am

You know the deal...
You know the deal…

We now have an electricity bill of $19.75, or 23.5 cents per day, which is even lower than my first full bill in July.

When you export enough energy to cover your service connection fee, you’re doing pretty well.

When you self-consume most of the rest, and only bring in a very small amount of peak power, that is obviously much better.

The Powerwall is essential to this plan, because it avoids peak tariffs using Reposit Power for tariff arbitrage.

That said, summer reality is starting to hit. As I write this, the outside temperature is creeping up toward 37oC (99oF). The air conditioner is running. Cloud cover is building as we head into the afternoon, and peak power tariff kicks in.

I’m taking this opportunity to experiment with the ducted air conditioner. I need to determine how to minimise cost without unduly affecting comfort levels.

Billing cycles will now fall roughly into quarters ending in October, January, May, and August. I need to think about maximising the two “good” periods, and mitigating the damage during peak summer and winter.

Of course, climate change might make the summer period even worse. That is something scientists already say is being felt, and will only increase.

The cosmic ballet goes on...
The cosmic ballet goes on…

Positive Billing Into The Future

How will things look this summer? There will be more sunshine than in winter, but more electricity consumption as well.

The data I have for the year ending January 2016 (when the system was installed) suggests summer usage is a couple of percent higher than winter.

Will this be offset by any exports I do? How does the temperature affect this calculation in terms of air conditioner use? Pool pump running? More events in warmer weather?

These are questions I can’t yet answer.

For now, I have 258 days of finalised bills, with a net electricity cost of $113.28 with referrals. That’s 43.9 cents per day for electricity, so I’m pretty stoked.

Even without the referrals, the figure is 71 cents per day, which is lower than my connection fee, and works out to $260 a year for electricity.

Even extrapolating the summer quarter as $1.30 per day (higher than winter), it works out to around $310 per year.

That still puts me in the box seat for a payback under 10 years, so its all systems go for now.

Relentless Self-Promotion Bit

Hey did you catch my recent video? I did a bit of off-road driving a couple of weekends ago. I’d love some more subscribers to my YouTube channel, so I can make more videos of things relating to solar panels and my own interests.

 

Tariff Arbitrage Using Reposit

Wait – what the heck is tariff arbitrage?

The general definition of “arbitrage” is:

… the simultaneous buying and selling of securities, currency, or commodities in different markets or in derivative forms in order to take advantage of differing prices for the same asset.

Clear as mud, hmm? That’s because the definition above relates to financial terms, and those financey guys are wizards of obfuscation.

Pictured: Wizard
Pictured: Yer a Wizard, Gordon!

Enough with the big words though. This is about finance, but not in the way Mr Stock Trading Person above understands it.

The practice of tariff arbitrage for electricity has a much more detailed explanation, but for me it breaks down to this:

Charge my battery when it is cheap, to use when it is not.

“Hang on – you have solar panels! Why do you need the arbithingees?”

I’m glad you asked, random internet person.

Tariff Arbitrage In Practice

Tariff arbitrage needs a set of circumstances to be useful.

Firstly, a battery to store the power. Solar is awesome, but it has issues with needing the sun. That generally means daytime, and not raining.

Secondly, you need the right electricity plan. When I was on single-rate electricity, I’d pay about 23c / kWh around the clock. Now I’m on TOU (Time Of Use), I pay off-peak of around 13c / kWh, and peak of around 33c / kWh.

Third, you need something smart to control all this, like Reposit Power. My Reposit box governs power flows between Solar PV, battery, and grid.

It has a learning engine for my household habits, so it knows when I’ll use power. Additionally, it can look at weather forecasts to see when I’ll have solar energy available.

These are two important things to know, because when I’ll use power and when the sun is shining are going to make a difference for my power bill. Particularly as I pay different rates for power when I use it.

A Graphic Example

Here is a screenshot of the (new) Reposit interface for my battery from this morning. I’ve edited the image to have two labels on it to show the power consumption.

Tariff Arbitrage 28 Oct 2016
29 October 2016 – Battery readout from Reposit web portal

Fairly typical for the household while we’re asleep. The Powerwall slowly draining as it feeds the fridge, any standby devices, and bathroom light for the kids. Only thing that changes is how much is in the battery to start with.

Here is the same screen but with data from the day before.

Tariff Arbitrage 29 Oct 2016
28 October 2016 – Battery readout from the Reposit web portal

Yowzah! It is going UP! And there is a reason for that: tariff arbitrage.

Yesterday, the forecast for Sydney was rain and heavily overcast conditions.

The Reposit software decided, based on the weather and my needs, that it should top up the battery to get me through the day. It uses the off-peak period to do that, and had actually commenced importing at 10PM the previous night.

This is the first time I’ve seen it top the battery right up. As you can see from the rest of the graph, I didn’t get through all this power in peak time. But I was buying it at a much lower cost than I’d otherwise pay.

How Low?

Here are the current rates I’m paying for Diamond Energy on TOU:

Rate Times Cost (c/kWh)
Peak
1PM-8PM weekdays
30.53 (0-340kWh per month),
31.49 (balance of kWh)
Shoulder
7am – 1pm,
8pm – 10pm weekdays,
7am – 10pm weekends / public holidays
24.97
Off-peak
All other times
13.84

Reposit Power aims to lower my costs. This decision to top up the battery is primarily for the peak period of 1-8PM where costs are at a premium. Once you take transmission loss into account (92% round trip efficiency on the Powerwall) I’m still ahead against Peak power cost by a ratio of 2:1.

Everything in between will mostly be taken care of by the trickle of Solar PV I generated during the day, as evidenced by the chart below.

Tariff Arbitrage Solar Gen
Solar Generation 28 Oct – high point noted for reference

This figure of 10.8kWh for the day is a long way from the 40kWh I’ve registered twice so far in October. But every bit counts.

Smoothing the Curve

Thinking about the solar figure jumping around a little, it also brings to light the other aspect of battery usage: curve smoothing.

When we have days with scudding* cloud and intermittent sunshine, a solar PV house with no battery is forced to call on the grid multiple times.

* Totally a word. Look it up.

Once the battery gets some juice in it, I’m less reliant on the grid for a sudden change in conditions.

Combine this with the automation of Reposit Power – where I don’t need to think about when the sun is out or not – and I’m onto a winner!

Reposit Power

System Upgrade

If you’ve ever looked at my System Specs page, you’ll see that I’ve got a fair bit of west-facing roof I don’t use. I decided to get an upgrade.

First port of call was Natural Solar, of course.

They looked at the system, and advised placing an extra six panels on the western roof. The same Phono Solar 250W panels would be used, each with a SolarEdge P300 power optimiser.

House Upgrade
Right about… there!

The two existing arrays tie back to the inverter with one string each. The new array would be joined onto the array to the left of picture (western). This made for the simplest install as it didn’t require new wiring to the inverter.

It also provided the benefit of generating from the sun in the afternoon. This is useful in the warmer months where I am more likely to use air conditioning.

Additionally, for those days that have overcast mornings, but sunny afternoons, I’d see the most benefit. Particularly true given the house has a rising ridge line to the east, so doesn’t see much sun early in the day.

With the detail sorted out, we agreed on a date for Splice Electrical to perform the upgrade. James and Nick turned up, and with their usual friendly professionalism, got to it.

While they were here I also got them to disconnect some old PSTN infrastructure that was slowing my NBN connection. Increased speed by 40%! Legends…

A few hours later I was the proud owner of another 1.5kW of panels!

upgrade complete. Now what?

Naturally, with an upgrade of this sort, you’re going to expect some improved results. The system has had a size increase of 30% (1.5 / 5.0 = 0.3). Would I get similar generation increases?

The main factor in all this is still the inverter. The SE5000 in my system is limited to 5kW in any direction. Therefore, expected generation, even with 6.5kW of panels, is limited to 5kW maximum.

I was quietly confident I’d hit this high mark regularly, given I generated 4.9kW or more at points during February and March, and even in May!

However, the panels aren’t in the same orientation as the rest of the system, so what is the effect?

Setting the baseline

According to one source, a solar PV system in Sydney should produce 3.9kWh per kW of installed panels per day. That is under lab conditions.

My initial system setup should (on average) have produced about 19.5kWh of electricity per day. For the lifetime of the system at 5kW, the SolarEdge API reports the following figure:


I hasten to point out that the data is a little murky. The SolarEdge API consolidates “generation” from PV and battery, because of the way it monitors flow.

Therefore, that figure only works if we’re assuming the battery is filled and drained every day. This certainly isn’t the case 100% of the time, but its enough to show we’re in the ballpark.

Another part of this is loss due to inefficiency. The Powerwall is about 92% efficient, meaning I have to spend around 1.5kWh of the 19.5kWh figure on the power going into and out of the battery.

The other factor is the timeline; we’re looking at a period from mid-February to early October. This includes the shorter daylight hours.

With all these factors considered, I’d say this is actually looking like a decent marker, even with the accepted error margin (+/- 10%) in the SolarEdge API.

Effect Of Upgrade

An extra 1.5kW of panels should result in a generation figure of 25.35kWh per day, on average, for Sydney.

The first caveat for this figure: it has been spankingly good weather in Sydney for the last week.

The new panels are also a different orientation to the others, which may affect the figure.

It is also a very small sample in terms of days. In the interests of science, I’ll leave this chart here to update daily. You can check in on it any time you like. A rolling 7- and 28-day chart is also on the Statistics page.

*drum roll*


Average just shy of 33kWh at time of print. Pretty good weather!

A better analysis might be to look at the curves being produced by the different panel setups. The figures aren’t as important as the shape of the curve.

That was from May, without daylight savings. The curve peaks around midday and is generally uniform. Pretty much what you’d expect. Decent result, too.

Now we throw another 1.5kW of panels on the western side, and add daylight saving to shift the curve to the right by an hour.

A small point: that is my record day so far. And its only October. Tee hee!

More importantly, we see the extension of the curve from the new peak around 1PM (daylight savings, remember), through until the late afternoon. We get a lot closer to sunset for generation as well.

The peak 5kW on this particular day hit at 1128 hours, and it stayed there until 1514 hours. The 5kW system infrequently reached 4.9kW, and then only for short stretches.

With the extra panels, not only is the generation figure much higher, but the long afternoon sun really kicks in.

Looking Ahead

As we move further into the warmer months, I expect the 5kW peak to be longer. Most likely, this will result in much more export until the point the ducted air conditioner is required on a regular basis.

I need to develop a strategy to mitigate that. Perhaps running the air conditioner in “continuous” mode on sunny days will help. This aims to keep the house cool, and the thermostat will lower the overall energy requirement.

I’m still finalising the change in payback time on the new array. Due to the move to TOU pricing, it is getting hard to keep all the facts and figures in order.

For the most part, I’m going to keep rolling calculations based on the single-rate plan offered by Diamond Energy. The rest of it makes my head hurt.

Powerwall Six Months On

Powerwall Six MonthsI’ve had the Powerwall six months now, or in fact a little longer. It would be more accurate to say I’ve had a functioning solar PV with battery system for seven months.

That dates back to when my meter was changed over to a basic bi-directional unit. Importantly, it is the date that billing with Diamond Energy started, with full and accurate detail of import and export.

I have had a  total of three bills, the most recent of which covers 52 days from mid-June to early August. It stops there because I’ve moved from single-rate to TOU tariffs, so Diamond decided to make things easier for calculation purposes.

The other two were covered by my blog post back in July. The full quarterly bill naturally received more attention than the one I hinted at in that post. With 174 days of billing data now in the bank, its time to look at a longer period.

This post will put up the basically points of interest from the three bills and their relevant statistics.

Powerwall Six Months Analysis – Part 1

The first bill covered the period of 17th February through to 23rd March.

Item Days Cost Import Export
Total 35 $23.89* 121 322
Average / day $0.68 3.46 9.2

* This amount removes the $20 establishment fee with Diamond ($22 inc GST)

With a connection fee of just over $0.82 / day, and an export tariff of 8 cents/kWh, I was almost covering the connection.

Of course, import was going to hit a bit harder in summer time. The last week of February was a record-setter in Sydney.

The temperature was minimum 26oC / 79oF for nearly the whole week. Frequently the temperature was over 35oC (95oF) in the late afternoon, hitting those big, west-facing windows. I can only sweat so much!

That kind of heat requires air conditioning, which you can see in the red spikes below.

SolarEdge Portal

It probably wasn’t even the amount I imported, more a case of when it was imported.

This is a small precursor to what you can expect from an Australian summer in this part of Sydney region. No ocean breezes this far inland.

During this period I clocked some fairly hefty production figures, topping out at around 34kWh, with several days in excess of 30.

The heat of a Sydney summer makes me a little cautious in regard to power usage. In addition to the extended hours for the pool, the heat will require air conditioning. That means import.

January tends to be the wettest month in Sydney, and storm season. Luckily, for those cloudy days and weeks I’ve got Reposit Power to do the thinking for me.

POWERWALL SIX MONTHS ANALYSIS – PART 2

The start date was 24th March, running through until 17th of June, 2016. This was the big quarterly bill which grabbed the media attention here in Australia, with a few overseas articles published as well.

I won’t go into too much detail as you can read about it here. The key data to consider

Item Days Cost Import Export
Total 86 $50.39 244 736
Average / day $0.59 2.84 8.6
Previous bill $0.68 3.46 9.2
Difference -$0.09 -0.62 -0.6

As you can see, the daily figures show slight decreases across the board.

At my import tariff, this equates to 13.2 cents / day decrease in costs as I’m importing less.

The export is 4.8 cents / day cost increase as I’m exporting less.

This comes out to 8.4 cents per day. The actual decrease of 9 cents per day is due in part to rounding.

Additionally, Diamond single-rate tariffs step up by a small amount once you use more than a certain number of kWh per month.

The weather during this period was pretty good. We had long weeks of sunshine, with few rainy days. The temperatures were very mild, meaning we didn’t need air conditioning or heating.

POWERWALL SIX MONTHS ANALYSIS – PART 3

The latest bill runs from 18th June through to 9th August, or a total of 52 days over winter.

In terms of “winter”, I should mention it never snows here. The closest snow I think fell about an hour’s drive away, in the Blue Mountains. It isn’t frosbite territory, and with the climate warming, isn’t ever likely to be. Short of another ice age, I guess.

We do get frosts, sometimes on consecutive days, and the lack of double-glazing, with basic wall and ceiling insulation batts, does mean the house gets cold. We also have a lot of tiled floor.

This bill gives a valuable insight into the changes that occur, in a period with less sun and more heating.

Item Days Cost Import Export
Total 53 $67.25 288 335
Average / day $1.27 5.43 6.3
Previous bill $0.59 2.84 8.6
Difference +$0.68 +2.59 -2.3

A little over double for daily cost, and the reasons why are fairly obvious.

Import rose by 91%, and export fell by nearly 27%. So it cost me an extra 50 cents per day for import and I missed out on around 18 cents for export. In the ballpark at 68 cents.

There were only a couple of days where we ran the heating longer than an hour or so. With the big motor on this ducted system, that was more than enough to start hitting the import hard.

Next winter, with TOU now in place, we’ll be a bit smarter. I’m talking to Reposit about the best ways to utilise off-peak power, and how their software handles it.

Note: the reason behind the short interval for this bill is replacement of my meter. The GridCredits scheme is reliant on a sophisticated unit, which I’ll put up video of when I get the time.

Summary

Putting all the information into a table gives a nice summary of the solar with Powerwall six months down the track.

Item Days Cost Import Export
Part 1 35 $23.89 121 322
Part 2 86 $50.39 244 736
Part 3 53 $67.25 288 335
TOTAL 174 $141.53 653 1393
Daily avg $0.81 3.75 8.01

Not bad, though of course I have yet to experience a full summer with this system.

Summer will mean more power imports as we use the air conditioning. It also means longer daylight hours. Greater export will offset higher import, to a degree.

Compared to winter, where heating and shorter daylight hours have clearly had an effect, summer should be slightly better. I’m still at the mercy of those 40oC+ days, but at least I can pay them back a bit.

Of course, as panel temperatures rise above 25oC, efficiency will drop. More light = more heat in summer, so I might not see many days above 35kWh with the existing system.

 

Autumn and Spring are looking like the “Kill Bill” (*snigger*) periods for the year. The milder weather and lower heating/cooling requirements are really where its at.

Powerwall Six Months
Not bad for 6th September…

Winter is going to be an issue ongoing, with lower daylight hours, and heating requirements. Summer will still need a lot of electricity imported, but can be offset with big exports.

The real challenge, moving forward, is to maximise self-consumption, and minimise waste. As always.

If I can keep the costs below $1 / day for my electricity, even with recent increases in tariffs, then I’m well on track to save $1900 in the first year. Maybe more after that!

Opportunity Cost Calculations

One of the outcomes of my recent bill were the articles written. Lindsay Handmer over at Gizmodo wrote an interesting piece about opportunity cost.

Opportunity Cost
A blast from the past! Aussie $50 note from 1973-1995

For those playing at home, “opportunity cost” is an economic term, defined as follows:

…the loss of other alternatives when one alternative is chosen.

In particular, looking at my statement about leaving the money in the mortgage offset account, versus buying the system.

I had confidently stated my preference for the financial outcomes of the system early on. As it was likely to save me (at least) double the value of my offset in terms of electricity savings, it looked like an easy choice.

Honestly, opportunity cost was not something I gave much thought to. I decided to invest the money in acquiring a hybrid solar system. I wanted to save on electricity bills, and the money looked well-spent.

What some may not know is Lindsay and I had a fairly long email discussion about the direction of the article. We checked facts and figures,and compared notes in terms of thought process.

The ultimate conclusion is the one that most basic analyses have come to; the Powerwall is not yet considered financially sound in terms of payback, against its warranted 10 years.

Estimates for payback vary widely on how you analyse it, and individual circumstances. I had calculated mine at around 8-10 years, and that looked good after the first bill produced savings of ~ $450 compared to same quarter last year (or about $1800 per annum).

A small diversion

One question I’ve been asked via various forums is “how much did the Powerwall contribute to those savings?”

Well, I could go full sarcasmo and say “100% because If I didn’t like Powerwall I never would have bought the system!” Obviously, that is no help to the realists 😉

Without digging into the nitty-gritty, I’ve looked at the figures and come out in this ballpark:

  • 50-55% Solar PV array in combination with time shift of usage
  • 25-30% Powerwall ability to store and deliver power in evenings
  • 15-20% reduction of usage – knowledge gained by SolarEdge and Reposit
  • 5-10% change of retailer – I didn’t really import much.

Make of that what you will. No doubt for winter, that will change a little as heating becomes a priority.

Moving forward, there will be other factors like my move to Time Of Use power and power arbitrage. Also there are battery-related initiatives like GridCredits that will help keep costs low.

Opportunity Cost

I got to thinking about my financials, since Lindsay’s article. During a subsequent proof read for another article I’ve written (to be published in the near future), I decided to go back and review “opportunity cost” as a thing.

I wondered if I’d made the right decision.

The article on gizmodo was right: while I was going to save on electricity bills, that money would no longer be helping slaughter my loan. By sticking it to the power company, I’d lost the chance to stick it to the bank!

What a conundrum…

I should mention that in the weeks before the install, I’d moved my mortgage to a product without an offset. I still could have dumped the lump sum it the mortgage directly, and let it ride.

But would I? Really?

Even in Aussie dollars, $16k is non-trivial amount of money to the average family. Maybe it was time to have a family holiday? Pay off some other debts? Do some enhancements around the house? Buy a GoT-themed jumping castle? Wait. What?

The point is, while its all well and good to say “stick it in the offset”, there are no guarantees that it would stay there. The problem with ready cash is that there are always things for which it could otherwise be used. Life happens.

Doing The Numbers…

For the sake of this discussion, let’s say the money went into the mortgage, for the Powerwall’s warranty period of 10 years.

Assume the interest rate stays at 4% (unlikely), and we keep any benefits in the mortgage. Under the principal investment of $15,990 the interest saved is $639.60 over the first year. Second year is principal $16,629.60 (adding the savings), which saves $665.18 and so on.

Now, based on rolling the principal + interest over every year, after 10 years we arrive at … carry the three … square the hypotenuse … divide by the tangential inverse of pi …

A total interest saved figure of $7,679.11 from my investment of $15,990.

Not bad!

I’ve continued to pay electricity bills during that time, of course.

Starting with my base usage costs of $1920 from the 12 months leading up to Powerwall, let’s be extremely generous to the retailers, and flag an upward move of 0.5% per year, on average.

That means in the first year the new usage costs are $1,929.60. Second year $1,939.25 – and so on.

Over 10 years, that little hike makes for a total electricity bill of $19,736…

I feel your rage, angry penguin... (c) Business Insider (click for page)
I feel your rage, angry penguin… (c) Business Insider

Therefore, despite saving money in my offset, I’m still down by a figure of just over $12k. If the price rise was just 2% per year on average, its more like $21,443.93 paid to the electricity retailer (loss of nearly $14k).

Just for reference, 2% increase on usage costs, for the average of 25 cents per kilowatt hour in these parts, is half a cent.

If the increase was 4% (1 cent per kWh), I’m paying out nearly $24k in electricity. That’s enough to cancel out the interest savings AND put me in the hole for the value of my system!

Now For Something Completely Different

Man. Who knew an increase of 1 cent could hurt that much?

Let’s take another tack, and look at using the money I save on electricity against the mortgage.

Again, we need to make some assumptions:

  • mortgage interest rate will be 4% ongoing
  • $450 saving on the first quarterly bill extrapolates to $1800 per annum
  • degradation in Powerwall is cancelled out by increases in electricity price
  • money saved on bills will be put back into the mortgage*

* Again, it probably won’t, but given the opportunity cost matrix assumes that all monies stay dedicated to the mortgage, I say game on!

Starting at Year Zero with a capital position of negative $15,990 we can compound all our numbers moving forward. Remember, we’re adding $1800 into the pot every year from bill savings, as compared to my old provider.

Therefore in the first year, we subtract $639.60 in lost interest from the starting capital position, but add $1800 per year in bill savings. That rolls over to the new amount for calculating the offset in the next year.

Year Lost offset Bill Savings Capital Position
0 n/a n/a -$15,990.00
1 -$639.60 $1800 -$14,829.60
2 -$593.18 $1800 -$13,622.78
3 -$544.91 $1800 -$12,367.70
4 -$494.71 $1800 -$11,062.40
5 -$442.50 $1800 -$9,704.90
6 -$388.20 $1800 -$8,293.10
7 -$331.72 $1800 -$6,824.82
8 -$272.99 $1800 -$5,297.81
9 -$211.91 $1800 -$3,709.72
10 -$148.39 $1800 -$2,058.11
11 -$82.32 $1800 -$340.44
12 -$13.62 $1800 $1,445.94

This indicates that some time very early in the twelfth year is when I hit payback, under the opportunity cost calculation. That would be the system paying itself off in full, and accounting for the mortgage offset.

Does It Really Matter?

Really, these numbers are just an exercise in maths. And a bit of fun.

It would be highly unlikely in either scenario, that spare money would sit in the mortgage that long. There are things to do, and locking up a bunch of money for a few percent interest until I’m in my 50s? Sounds like wasted beer money, or holiday money, or holiday beer money.

Beyond the first year will I really save $1800? Will the addition of Reposit Power improve things further? What happens when the interest rate on my mortgage shifts?

Trying to cater for all these factors could drive a bloke crazy.

Looking at the opportunity cost is an interesting exercise, but it won’t keep me up at night. I’m hardly tying myself in knots with post-purchase cognitive dissonance either. I have a power bill that makes me smile.

There are also intangible benefits I’ve had on a personal level.

My rough biscuit has been on TV a few times, and across other media, which was a bit of fun.

I have created a little corner of the internet to blather my thoughts into the ether, and I’m flattered that people read it!

One of the best parts has been meeting with switched-on people, who want to make a real and positive change. They have a lot to teach, and I am in awe of the chance to learn from them.

You can’t put a price on that.

Energy Networks Conference

While I was in Melbourne last month, the guys at Reposit Power contacted me to see if I was interested in attending Energy Networks 2016.

Energy Networks 2016

This is a conference for Energy Networks Australia, whose members make up the industry responsible for building and maintaining the poles, wires, pipes, substations, and other media for distribution of electricity and gas services.

“Oh you mean those guys who send me the damn bills every month?!!”

Well, no. That is your retailer and its important to understand the difference. The AER (Australian Energy Regulator) website describes the distribution networks clearly:

Electricity and natural gas distributors own and maintain the distribution networks, including electricity powerlines and power poles, and natural gas pipelines that carry electricity and natural gas to houses and businesses.

Your retailer is the company with the relationship to you. The Distributor – usually referred to as the Network – is the company building and maintaining the hardware.

My electricity retailer is Diamond Energy. I have an agreement with them whereby I pay for electricity usage in my house, including an agreed price per kWh and daily connection, as well as my feed in tariff (FiT) for exporting solar power. If I have any questions over my billing or service, I go to Diamond.

Diamond Energy sell their product to me via a network owned and maintained by Endeavour Energy (the Network or Distributor), who are responsible to ensure the network is up and running. If there is an outage, Diamond talk to Endeavour about resolution, and feed information to me.

The Network is focused on a working system, and the Retailer is focused on a happy customer. Classic, two-layered B2B (Business To Business) situation, operating in parallel with a B2C (Business To Customer) relationship.

On to Energy Networks 2016

I decided it would be pretty cool to take a few days off work, and go see how the big end of town do things. Trains, planes, and automobiles later, I was in Adelaide.

OK,  its DISCLAIMER time: Yes, I was there as a guest of Reposit. No, I was not under any instructions to say certain things or do certain things. You can believe what you wish in that regard, and you probably will!

All I know is I’ve seen the technology at work, and it is good.

While wandering around the displays, I saw a lot of people who are high up in the industry domestically, such as CEOs and COOs and other positions with abbreviations starting in “C”.

There were also overseas players like Enphase CEO Paul Nahi, who was in town to get a look at the scene, and back up their announcements about working in Australia.

Our nation is gunning for a leading role in battery implementation, to go with its solar PV penetration rate. If only our governments would see this and pull their finger out …

Of course, a few ruffians were about the joint like Giles Parkinson and Finn Peacock, to report on proceedings and relay the vibe.

It was slightly unusual that Reposit were bringing a customer to see the Networks, without a Retailer necessarily being in the way. The reasons why are down to what Reposit is offering to all layers of the market.

I discussed the ins and outs of Reposit in a previous post, mainly from my own point of view, alluding to the advantages an on-grid battery can offer everybody in terms of an available power resource.

An Important Step

Things just got real in light of an announcement made last week by SA Power Networks (SAPN), the Network Distributor for South Australia.

They will be engaging 100 households in a Residential Battery Storage Trial in the Salisbury area, in the northern suburbs of Adelaide.

This is huge for customers, as they will benefit from installation of a subsidised system with either a Tesla Powerwall or Samsung ESS battery. Lower bills are practically guaranteed.

It gives the Network an unparalleled look at how battery technology can smooth peaks and troughs, and give them on-call resources in addition to existing generation. It may also help reduce network implementation and maintenance costs.

The smarts at the centre of systems installed? Reposit.

Bringing The Tech

Energy Networks

That’s Dean Spaccavento, one of the founders of Reposit, being interviewed at the stand on Thursday. Good hustle!

In that shot, you can see a Macbook, which is running a live demonstration of the Reposit Marketplace application. This allowed networks to understand the capabilities Reposit from the back end, including the virtual power station concept.

The consumer end was demonstrated with a new iOS app, and as this involved dispatching power from my Powerwall, I made a couple of dollarydoos over the course of two days, which was a nice little bonus.

Together, the applications aptly demonstrated solving the problem for the network, and bringing the user into the circle of trust.

Along with a detailed rundown on how the Reposit Box makes decisions on behalf of the consumer, it provided a really good look at not only how the products work in theory, but how they were going to be applied for the SAPN trial. It is a very tasty thing to get a feel for it, while knowing a real-world scenario available for analysis over the coming months.

In addition to the Reposit team talking about technical aspects of the system, I personally fielded questions about where I sat as a consumer.

Understanding The Customer

For networks, the experience of battery users to date has tended toward those who want to get off the grid altogether, for two primary reasons:

The lifestyle consumer wishes to live in a location the grid can’t service today, typically in a rural area where land is cheaper. The capital cost of extending poles and wires can be prohibitive, so a battery system is often a better option, financially. At the same time, these people seek to build an efficient house, investing up front to ensure ongoing costs are minimal.

The combative consumer no longer wishes to pay for what they see as extortion from either the network, retailer, regulator, or government. Sometimes a combination of two or more. They tend to be older, cashed up, and technically minded. They’re ready to leave the grid at the drop of a hat, regardless of where they’re located.

In both cases, it is a very small percentage of households who can afford to take the option of off-grid living. Most of us don’t have money for enough batteries and solar panels to get us through a week of wet weather, and can’t even fathom being away from the safety of the grid.

Energy NetworksNow, with the advent of smaller lithium storage tech, the networks and retailers are going to need to deal with a third type of consumer: the grid-connected battery user.

How to address this?

I suppose, after talking to a few people from the industry, some of whom alluded to specific service issues they were having in their backyard, the message I want to broadcast as a user is: don’t panic!

We Don’t Have Horns

A lot of us like having electricity that is reliable, safe, and affordable. While some might complain about their electricity bill, the fact is electricity still isn’t the biggest cost factor in a lot of households.

We’re not all about to up and leave the grid because Elon Musk mentioned it was a possibility. In a lot of cases, it still isn’t financially practical.

I spent a fair bit of money and solar + storage, and still have days where I run out of battery, or don’t fill it up. So I need the grid, because I don’t want to leave my family stranded. I also need fresh water connection and gas to cook with. This is all part of modern living.

What we want, as consumers, is to be treated fairly when it comes to giving you access to resources that we paid for. After all, it is what you expect in return for your resourcing of the grid.

Mistakes were made when it came to some of the early gross tariffs. Uptake of systems with a FiT of 40 cents / kWh or higher were higher than expected, probably due to poor planning.

That doesn’t mean the users contributing their exports outside those schemes should be given a rate approaching 50% of off-peak, either. It wasn’t our fault the government got a bit trigger-happy and / or gun shy about solar systems back in the 2000s.

Potential Solution

I don’t really have a problem with solar export being paid at rate smaller than the single-rate import tariff. And I realise a lynch mob will be after me for saying that.

It comes down to simple economics: as you can’t guarantee supply of solar from rooftop panels, you can’t expect to charge the same as a guaranteed supply from the grid. That said, 5c / kWh is bloody ordinary.

It might not matter for much longer, because batteries change this dynamic – I absolutely can guarantee the delivery of power from my battery.

It is stored, often idle, and usually ready to go during the day by 1PM, with about 6kWh to deliver outbound. Get hold of another 100-200 users with varying battery types, and that might be a Megawatt or more, to help you fill a hole.

Particularly with Reposit managing my usage, I’m confident that most days I’ll be available for you, provided I’m going to get fair recompense for use of my resources. After all, if you come to me, chances are its cheaper than going somewhere else.

I can see a point in the future where solar feed-in-tariffs are no longer used, because it will so be advantageous to own a battery and keep a steady stream of electrons moving through it, rather than from the panels. Retailers will run to this solution, and networks will benefit.

Its just a question of how the reward will be calculated.

Getting To Know You

The first step for any Network stepping into this brave new world might be a tighter relationship with Retailers, and disseminating information you have on where the industry is headed with batteries. In turn, they can share with you their experiences, and what they’re seeing out in customer land.

Together, you can get schemes like GridCredits moving, with early intervention to prevent another financial blowout like Gross Tariffs. Can’t leave these things to the government, based on experience so far.

Will you look to have a flat rate like Diamond Energy’s GridCredits 100 scheme? Can you leverage your existing market spot rate calculations to flow through to users or chip a little bit of profit off that? Those are big money questions that this IT guy doesn’t have answers to. Its a work-on for you and the rest of the industry.

It might even be that you need to provide information on the practical costs of peak demand to the consumer base, in order to give users a view that goes beyond a perception of simple greed.

Of course, there are some people you’ll never convince otherwise 🙂

You’re still unlikely to see mass defections from the grid, but as the price of batteries drops, certainly more people are going to investigate the outlay to do so.

Increase in batteries and PV is going to see a decrease in grid usage against projected growth, which is already softening on a per-capita basis. This might affect profitability, particularly where a network needs to be extended to reach a growing population.

http://www.tradingeconomics.com/australia/electric-power-consumption-kwh-per-capita-wb-data.html
Power Consumption Per Capita in Australia Credit: Trading Economics (click image for link)

One of the facets of SAPN’s trial is to look at mitigating network capital costs by using the network resource that is user batteries. I’d be paying close attention to that, particularly where you are responsible for remote networks that require backup diesel generators etc.

How To Engage Consumers?

This is the multi-billion dollar question. As you may have surmised, I’m quite engaged.

Since this whole Powerwall thing landed in my lap, I’ve made it almost my second job to know everything I can know about how to most efficiently use the resources I have.

In this, I’ve been helped by companies like Natural Solar and Reposit Power, and I consider myself reasonably well-informed as a result of their input.

I follow sites like Renew Economy and filter their comments section to see where users are. Once you chop out the mad hatters, its very interesting to see where other consumers sit.

The rest of your customer base are probably going to tail away from that in terms of knowledge, right down to those who don’t understand the difference between Network and Retailer. They need help.

There is a wealth of data there, in terms of human feedback, that you – and the Retailers – need a relationship with. It will serve you well in the long term.

I shall sign off by imagining myself back in a trendy bar in an Adelaide laneway, hoping everyone looks forward to this bright new battery future as much as I do.

Bar

P.S. In terms of awesomeness: besides Reposit, the guys from Redstack have to rate right up there. Their UAV with 3D-printed parts was totally rad. WANT.