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Over the last 3 years, our solar panels in London generated 12MWh of electricity. We sold 7MWh back to the grid. And we only imported 7MWh. Basically, we're p

by edent 3y ago

Over the last 3 years, our solar panels in London generated 12MWh of electricity. We sold 7MWh back to the grid. And we only imported 7MWh. Basically, we're power neutral right now. A standard UK roof can easily generate an average household's electricity use across the year. Panels are likely to get cheaper and more efficient. At current prices, solar panels pay for themselves in under 8 years. Batteries are harder. Our 4.8kWh battery means our electricity bill for August has been practically zero. As we go into winter, we'll switch to a tariff which does cheap overnight charging so we can arbitrage on cost. Personally, I think big batteries for communities make more sense - the current domestic ones are big, noisy, and have a far longer payback time. For less than the subsidy of one nuclear power station, we could give every home in the UK a 5kW solar installation. (Yes, I know it isn't that simple.) Solar has convincingly won. But the inertia of the old way of doing things will take a little time to correct.

phil21 3y ago
> As we go into winter, we'll switch to a tariff which does cheap overnight charging so we can arbitrage on cost. "As we go into winter, we will leverage the super cheap battery poor folks are forced to pay to exist for us when it's convenient". It's very hard to take these arguments seriously when that is really what is happening - relatively well off folks using the commons to subsidize themselves whilst patting themselves on the back about it. Yes, it's a quite trivial problem when you get to outsource the hard bit of it and only have to pay for the low hanging profitable fruit. Until your community battery gets into the weeks to month in storage capacity, these anecdotes really read disingenuous to me. Seasonal storage is the hard nut to crack, and we haven't even solved overnight storage for most places. I've been spec'ing out truly off-grid designs lately, and it's an order of magnitude difference if you want to not use the public subsidy of your neighbors paying for it for you.
htss2013 3y ago
How does that work in the winter in England? You'd think such a climate wouldn't work well with solar except in the summer, and not summer is most of the year. I assume you're using gas or other sources for heating?
glogla 3y ago
> Solar has convincingly won. > As we go into winter, we'll switch to a tariff which does cheap overnight charging so we can arbitrage on cost. Seems it really didn't. What is your plan for the new way of getting electricity in winter?
- edent 3y ago
  Sadly, I can't install a wind turbine in my garden. So I'm buying the electricity from the ones down the street from me. But, except when they're literally covered in snow, my panels still chug along.
  - benj111 3y ago
    Snow? In London?
thebruce87m 3y ago
A reminder that England != UK != London. > It is important to be aware that different regions in the UK have different sun hours per day: England has 4.1, Scotland has 3.7, Northern Ireland 3.2 and Wales 3.3. https://www.greenmatch.co.uk/blog/how-many-solar-panels-do-i-need https://www.greenmatch.co.uk/blog/how-many-solar-panels-do-i... Not disagreeing with what you’re saying, but your numbers will be different than mine.
- edent 3y ago
  Sure, but with a battery the number of "sun hours" becomes less relevant. A sun hour is a somewhat made-up term for when you can get 1kW per square m. But if you're not using much power at sunrise, that's still enough to charge your battery. Even in Scotland, you can still hit your targets with a modestly sized array - https://re.jrc.ec.europa.eu/pvg_tools/en/tools.html https://re.jrc.ec.europa.eu/pvg_tools/en/tools.html
ghusto 3y ago
> At current prices, solar panels pay for themselves in under 8 years. and from the article > the discussions seem stuck back in 2010, when solar power and electric vehicles were prohibitively expensive It's an inconvenient truth that most people can not afford to pay €20-40k for something now, that will save them money in 8 years (and then, slowly). As the saying goes "it's too expensive to be poor" — except we're all "middle-class" now, apparently.
- edent 3y ago
  A typical solar array and installation is anywhere from £4k - £12k (a bit more if you want a battery etc). I agree that we should be subsidising the installation. And, indeed, lots of councils do group-buying schemes which do that. And there are semi-reasonable financing schemes available.
- crazygringo 3y ago
  That's what financing is for, although its availability is dependent on what a bank can recover if you stop paying -- e.g. they can take back your car or repossess your house. Installation costs can't be recovered, but a battery can certainly be repossessed. Unmounting solar panels is probably much more work, so I don't know. Or just add it to your home's existing mortgage, since then it's just repossessing the house with solar+battery included. But the point is that, if the down payment is made small enough, the desired result is that you start saving money immediately, because your monthly financing payment is less than what you're saving on your electric bill. Of course, ideally there's some kind of government subsidy here that makes it a no-brainer for banks, where the government pays the interest or down payment or something.
  - tomatocracy 3y ago
    There are schemes in the UK which will allow you to add these costs to your energy bill (repaid over time with interest). This seems to me like the "best" solution - it puts the costs and benefits together, stays with the house and the bad debt risk is significantly mitigated without needing to worry about enforcing security over a physical asset. Not sure why it's not better known or widespread.
Gibbon1 3y ago
I think the big thing that happened in the last few years is containerized utility battery systems are now a win purely based on balance sheet accounting. The logistics are really good. You can manufacture them in a factory. Ship them as a normal container. Drop them where they can be conveniently connected to the grid. And that's it.

by edent 3y ago

phil21 3y ago

> As we go into winter, we'll switch to a tariff which does cheap overnight charging so we can arbitrage on cost. "As we go into winter, we will leverage the super cheap battery poor folks are forced to pay to exist for us when it's convenient". It's very hard to take these arguments seriously when that is really what is happening - relatively well off folks using the commons to subsidize themselves whilst patting themselves on the back about it. Yes, it's a quite trivial problem when you get to outsource the hard bit of it and only have to pay for the low hanging profitable fruit. Until your community battery gets into the weeks to month in storage capacity, these anecdotes really read disingenuous to me. Seasonal storage is the hard nut to crack, and we haven't even solved overnight storage for most places. I've been spec'ing out truly off-grid designs lately, and it's an order of magnitude difference if you want to not use the public subsidy of your neighbors paying for it for you.

htss2013 3y ago

How does that work in the winter in England? You'd think such a climate wouldn't work well with solar except in the summer, and not summer is most of the year. I assume you're using gas or other sources for heating?

glogla 3y ago

> Solar has convincingly won. > As we go into winter, we'll switch to a tariff which does cheap overnight charging so we can arbitrage on cost. Seems it really didn't. What is your plan for the new way of getting electricity in winter?

edent 3y ago
Sadly, I can't install a wind turbine in my garden. So I'm buying the electricity from the ones down the street from me. But, except when they're literally covered in snow, my panels still chug along.
- benj111 3y ago
  Snow? In London?

thebruce87m 3y ago

A reminder that England != UK != London. > It is important to be aware that different regions in the UK have different sun hours per day: England has 4.1, Scotland has 3.7, Northern Ireland 3.2 and Wales 3.3. https://www.greenmatch.co.uk/blog/how-many-solar-panels-do-i-need https://www.greenmatch.co.uk/blog/how-many-solar-panels-do-i... Not disagreeing with what you’re saying, but your numbers will be different than mine.

edent 3y ago
Sure, but with a battery the number of "sun hours" becomes less relevant. A sun hour is a somewhat made-up term for when you can get 1kW per square m. But if you're not using much power at sunrise, that's still enough to charge your battery. Even in Scotland, you can still hit your targets with a modestly sized array - https://re.jrc.ec.europa.eu/pvg_tools/en/tools.html https://re.jrc.ec.europa.eu/pvg_tools/en/tools.html

ghusto 3y ago

> At current prices, solar panels pay for themselves in under 8 years. and from the article > the discussions seem stuck back in 2010, when solar power and electric vehicles were prohibitively expensive It's an inconvenient truth that most people can not afford to pay €20-40k for something now, that will save them money in 8 years (and then, slowly). As the saying goes "it's too expensive to be poor" — except we're all "middle-class" now, apparently.

edent 3y ago
A typical solar array and installation is anywhere from £4k - £12k (a bit more if you want a battery etc). I agree that we should be subsidising the installation. And, indeed, lots of councils do group-buying schemes which do that. And there are semi-reasonable financing schemes available.
crazygringo 3y ago
That's what financing is for, although its availability is dependent on what a bank can recover if you stop paying -- e.g. they can take back your car or repossess your house. Installation costs can't be recovered, but a battery can certainly be repossessed. Unmounting solar panels is probably much more work, so I don't know. Or just add it to your home's existing mortgage, since then it's just repossessing the house with solar+battery included. But the point is that, if the down payment is made small enough, the desired result is that you start saving money immediately, because your monthly financing payment is less than what you're saving on your electric bill. Of course, ideally there's some kind of government subsidy here that makes it a no-brainer for banks, where the government pays the interest or down payment or something.
- tomatocracy 3y ago
  There are schemes in the UK which will allow you to add these costs to your energy bill (repaid over time with interest). This seems to me like the "best" solution - it puts the costs and benefits together, stays with the house and the bad debt risk is significantly mitigated without needing to worry about enforcing security over a physical asset. Not sure why it's not better known or widespread.

Gibbon1 3y ago

I think the big thing that happened in the last few years is containerized utility battery systems are now a win purely based on balance sheet accounting. The logistics are really good. You can manufacture them in a factory. Ship them as a normal container. Drop them where they can be conveniently connected to the grid. And that's it.