Solar Panels

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lpm
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Re: Solar Panels

Post by lpm » Sat Nov 06, 2021 2:18 pm

Tesla installations are double the price.

Shows the power of a brand name but even the Teslarati tend to steer clear.
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Grumble
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Re: Solar Panels

Post by Grumble » Sat Nov 06, 2021 7:31 pm

lpm wrote:
Sat Nov 06, 2021 11:52 am
Sling around your referral code, Grumble, it seems worth the £25 reservation fee.
Certainly, it’s https://rippleenergy.com/?ogu=2236
A bit churlish

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nekomatic
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Re: Solar Panels

Post by nekomatic » Mon Nov 08, 2021 12:13 am

I have been seeing ads on Facebook for ‘free solar panels’ for ages, but this week I started seeing ads for ‘have you been missold solar panels?’
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Re: Solar Panels

Post by Woodchopper » Mon Nov 08, 2021 7:33 am

lpm wrote:
Sat Nov 06, 2021 11:52 am
Grumble wrote:
Sat Nov 06, 2021 9:46 am
I do think sharing in a wind farm is better for an individual though. I haven’t actually bought shares yet, just reserved the chance to do so for the next build. Ripple have already built one shared ownership wind turbine so it’s not pie in the sky. I’d welcome critical analysis of the numbers before I actually put significant money into it, I’ve been convinced by their sales pitch but I’m no economic expert.
The Ripple co-op has similar economics to the other schemes, I think. But a hell of a lot easier than getting solar or batteries - 5 minute task instead of the pain of roofers and scaffolders and electricians.

For context, battery guy was talking about a £3,900 investment and solar would be something like £6,000.

For the second project they estimate approx £1,500 investment to get approx 8kWh per day. So in CO2 terms that would basically cover my background house usage. That's much more appealing CO2-wise than paying for solar.

In financial terms you don't get the 8kWh per day for free, however. If I understand it right, you sell your bit of the generation to Octopus or Co-op for about 5p per kWh. Then you choose Octopus or Co-op as your supplier and take one of their usual tariffs on offer, say 25p. They apply your generation back on to your bill as a 5p discount. You get your own electrons back, sort of, but buy them back at less than you sold them.

5p per kWh discount translate to £145 saving p.a.

Which isn't great, compared to investing £1,500 into my pension. But it's almost identical to battery guy's £401 p.a. saving for a £3,900 investment.

Currently it looks like the discount is more like 8p, due to the sky-high electricity prices, while the first project had an assumption of 4p. Owning a fragment of a wind turbine is a bit more profitable when prices go up, obviously, but hard to make a guess on where they'll be for the next decade or two. If you own a wind farm you pray for windy days but then moan because the wholesale price on windy days is so low. Assuming 5p seems OK as a base case.

One slight issue is that (currently) it compels you to take Octopus or Co-op as your electricity supplier. Maybe alternatives will be added in the future. Octopus is actually what I want right now, because they're the ones that offer 5p night rate for EV charging. But this might all change in five years, with alternative suppliers becoming cheaper or Octopus going bust or whatever. Tying yourself down isn't attractive.

A big plus is that you can move house and take the investment with you, unlike solar. So ideal for anyone planning to move. You can also invest into Ripple itself, for a modest sum, but the exit strategy for ever selling this investment again is a bit shaky.

They don't seem to mention tax on their website. I bet the £145 p.a. saving would be treated as a dividend and taxable. Although the personal dividend allowance, if it still exists, would typically cover it.

When my EV finally shows up I'll be going from an average of 9kWh per day to about 14. Covering the CO2 would require an investment of approx £2,650 for annual savings of about £260. The car itself would be about £900 of this investment. To be honest I've paid £650 for a nice colour. And £650 for stupid alloy wheels because the standard ones were so ugly. And the home charger will cost £600. And I might spend an extra £400 on the charger to get a really pretty one. Amidst this frivolity refusing to spend £900 to increase the UK's wind generation seems a bit perverse.

I'm thinking the financial investment calcs are just about enough to justify Ripple, because CO2-wise it's so much better than batteries, and so much less building hassle than solar. It would be good fun to see how it plays out over the next couple of decades, plus smug-points for knowing exactly where your home's renewable energy comes from.

Sling around your referral code, Grumble, it seems worth the £25 reservation fee.
That all looks correct.

But it seems to me that in the future an important reason for buying a big household battery would be security of supply. That's not something that most people in Britain have had to think about as prices have been relatively stable and lengthy power cuts have been rare. However, a future with far more renewable power generation might see interruption sin supply - eg a January evening when there is much less wind than usual. That may result in big spikes in prices by companies as part of demand management, or even power cuts.

Of course large scale communal batteries would be far more cost efficient. But then individual households would need to trust that there would be enough capacity for all. If they don't then a home battery that's charged when power is cheap and discharges when its expensive would make sense.

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Re: Solar Panels

Post by IvanV » Wed Nov 10, 2021 4:58 pm

kerrya1 wrote:
Fri Nov 05, 2021 9:25 am
Thanks Ivan, this is all helpful. My husband and I both work from home at least 4 days a week so we would be using the energy generated during the day - I wouldn't be considering it if the house was empty all day. We do have all LED bulbs and an induction hob, all our applicances were as efficient as possible when bought and new enough not to need replacing soon. The house does need cavity wall insulation and better loft insulation, but that is also part of the plan and would be done before or alongside any solar installation. We also have an attached garage where we could install a battery.

My brother lives in the Borders and has recently replaced their oil fueled central heating system with an air source heat pump but as we are in a suburb of Edinburgh I don't think we'd go down that route. I have looked at solar water heating but I'm not convinced, yet, our electricity usage is much more significant than our gas as it only provides the heating and hot water, everything else is electric. Do you have any thoughts on the combined Solar PV and water heating panels?
Have you got a smart meter with an In-Home Display (IHD)? If so, it should show your electricity consumption by the half hour for the last 24 hours, or something like that. Alternatively, your electricity supplier may, if you give them permission, take a reading as frequently has every 5 minutes, if you have a smart meter. So depending upon the user-friendliness of your supplier's webpage front end, you can potentially get more granular data by downloading it from their website. (I have Octopus and it seems they don't have a bulk data download option, or at least I haven't found it; though my previous supplier did, but it no longer exists as it was taken over.)

So I just went and had a look at my IHD. Like you, I work from home most of the time, and my wife 2 dpw also. But I have been using a little under 100W in most daylight hours today, a dim drizzly November day requiring internal lighting, with two computers switched on, wifi, two fridge-freezers and another freezer, and the central heating switched on and pumping water to the radiators from time to time. In summer the fridges would use more, but wouldn't need the lighting or heating. That's a pretty normal base level of consumption for us. I expect to see the house to run at around 70-90W most daylight hours when the house is occupied but no heavy energy-using appliances are running. I did run a heavy energy using appliance for a while today, and so used 600-700W for the period when that was on. So I used almost 10 times as much electricity in the 4 half-hours that applied. That was baking a loaf of sourdough bread in the oven at 250C (500F). Makes an absolutely massive difference to our energy consumption at a half-hourly level. Unfortunately home-baked sourdough is not a very CO2-friendly activity.

If you had 4 kW of solar panels on your roof, most daylight hours in the year, even in dim Scotland (you are lucky - Edinburgh has one of the sunniest micro-climates in Scotland), you are going to be vastly over-serving a sub-100W hourly demand. And the excess will be spilled out into the grid, at poor value to you. Though you can argue you are reducing Scotland's CO2 emissions, if you don't care about getting much financial reward from it, and it being a rather expensive way of achieving it. Then when you turn some heavy energy-using appliances on, your solar cells often won't be putting out enough to serve them.

In fact the situation is potentially even worse than that overview suggests. My electricity consumption looks quite smooth at a 30 minute granularity shown by my IHD, aside from when I turned the oven on. But if it showed it second by second, which is what your electricity meters are going to record as they accumulate how much electricity you import or export from the grid, then it becomes much more lumpy. You turn a 1.5kW kettle on for a couple of minutes to boil some water. During that brief time, often your 4kW panels aren't going to serve all that, so you'll have to import some electricity for that brief time. But that will actually be a significant part of your electricity consumption in that half hour. Similarly, the oven is controlled by a thermostat. So it is going to oscillate between drawing something like 3kW and nothing. So when it is drawing 3kW you are going to have to import from the grid, and when it switches off, you are going to have too much again. So even if your 4kW solar panels were producing 700W, it wouldn't actually be able to serve very much of the oven demand averaging 700W, because that 700W is an average between short periods of 3kW and longer periods of nothing.

A Tesla Powerwall 2, for example, will give you 4.6 kW maximum output and 13.5 kWh capacity. As you can see from the above discussion, it is quite easy for a house to instantaneously reach something approaching 4.6 kW, usually when you are cooking and may have other appliances running. You do need an output level something like that to cover the very short term swings of a normal household's electricity demand. But 13.5 kWh in capacity is probably a lot more than you can really profit from. It would mean you wouldn't have to export very much of your solar electricity even in a bright week at the bright time of year. But most of the time it's going to be too much to deal with your short-term swings, and most of its capacity will be of poor value most of the time.

These very large swings in consumption second by second are why it makes a lot of sense to have shared facilities across a community, to smooth it out. Otherwise called the grid - and I'm referring to the local distribution grid here, not grid-connected in the sense of directly connected to the National Grid. So if there are to be batteries, it makes much more sense for them to be grid-connected and hence shared across a community. If there are to be solar panels,it makes much more sense for it to feed the grid, and so serve instantaneous demand where it is present. Where it goes wrong, unfortunately, is in the system of charges and payments for those grid entries and withdrawals.

I have no knowledge either of solar water heating performance in Scotland, nor of hybrid solar heating/PV cells.

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Re: Solar Panels

Post by kerrya1 » Thu Nov 11, 2021 11:29 am

Thank you Ivan, this is really helpful and combined with the other research I've been doing I don't think we'll go ahead with the Solar Panels in the short term at least.

Instead we'll focus on making the house as insulated and energy efficient as possible, and training the kids to turn the bl..dy lights and TV off when they leave the room.

Kerry

P.S We do have a Smart meter but it hasn't worked since it was installed about two years ago, I'm waiting for EDF to replace it.

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Re: Solar Panels

Post by lpm » Thu Nov 11, 2021 11:39 am

Convert to LEDs and the bl..dy lights make zero difference. And the TV is near zero difference.

If electric shower, taking a shorter shower helps. Keeping the oven on for a minimum time. No tumble drier. Avoiding electric heaters. Not overfilling the kettle is a good one to train the kids on.

And choosing highly efficient white goods as they come to the end of lives and need replacing.

And ultimately choosing an efficient EV and driving it efficiently - a mile of driving will be the equivalent of leaving a TV on all day, ballpark.
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plodder
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Re: Solar Panels

Post by plodder » Fri Nov 12, 2021 8:20 am

Don’t fly as much. Eat more veg. Smash patriarchal capitalism.

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Re: Solar Panels

Post by kerrya1 » Fri Nov 12, 2021 9:22 am

plodder wrote:
Fri Nov 12, 2021 8:20 am
Don’t fly as much. Eat more veg. Smash patriarchal capitalism.
Haven't flown anywhere in 10 years, gradually converting family to vegetarian (down to meat two meals a week, and fish one), not sure how to do that last one, but happy to help.

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Re: Solar Panels

Post by plodder » Fri Nov 12, 2021 10:01 am

kerrya1 wrote:
Fri Nov 12, 2021 9:22 am
plodder wrote:
Fri Nov 12, 2021 8:20 am
Don’t fly as much. Eat more veg. Smash patriarchal capitalism.
Haven't flown anywhere in 10 years, gradually converting family to vegetarian (down to meat two meals a week, and fish one), not sure how to do that last one, but happy to help.
I'll put you on the list as a helper, thanks

:D

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Re: Solar Panels

Post by nekomatic » Sat Nov 13, 2021 12:00 am

It’s been said here before but bears repeating: if you want to put a few grand of capital into renewable energy or energy efficiency, go on to somewhere like Ethex and invest it in some schemes where somebody else is doing something with greater impact than sticking panels on your own poorly insolated roof.
lpm wrote:
Thu Nov 11, 2021 11:39 am
No tumble drier.
If you have a room with space to put up a drying rack, or install one of those ceiling pulley uppy things, get a dehumidifier and leave the two of them to get on with it. This has completely transformed our laundry experience. The dehumidifier uses about four hundred watts.
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Re: Solar Panels

Post by kerrya1 » Mon Nov 15, 2021 7:36 pm

nekomatic wrote:
Sat Nov 13, 2021 12:00 am

If you have a room with space to put up a drying rack, or install one of those ceiling pulley uppy things, get a dehumidifier and leave the two of them to get on with it. This has completely transformed our laundry experience. The dehumidifier uses about four hundred watts.
This is exactly the set up we currently have, pulley and a couple of laundry racks that can hold 2-3 loads of laundry paired with good dehumidifier. When the weather is dry it all gets hung outside which is the most energy efficient of all.

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Re: Solar Panels

Post by lpm » Tue Feb 08, 2022 11:37 pm

Grumble wrote:
Sat Nov 06, 2021 7:31 pm
lpm wrote:
Sat Nov 06, 2021 11:52 am
Sling around your referral code, Grumble, it seems worth the £25 reservation fee.
Certainly, it’s https://rippleenergy.com/?ogu=2236
Looks like Ripple 2 is about to launch, if anyone wants to jump on board.
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Re: Solar Panels

Post by bmforre » Wed Feb 09, 2022 4:36 am

nekomatic wrote:
Sat Nov 13, 2021 12:00 am
If you have a room with space to put up a drying rack, or install one of those ceiling pulley uppy things, get a dehumidifier and leave the two of them to get on with it. This has completely transformed our laundry experience. The dehumidifier uses about four hundred watts.
Humid air contains considerable heat used to evaporate the water that makes this air humid. The dehumidifier regains this heat as it makes the humidity re-condense. So a good dehumidifier can be an efficient heatsource, not a watt-waster: It will emit the sum of the heat from own electric losses plus heat of condensation. :)

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Re: Solar Panels

Post by bjn » Wed Feb 09, 2022 8:20 pm

lpm wrote:
Tue Feb 08, 2022 11:37 pm
Grumble wrote:
Sat Nov 06, 2021 7:31 pm
lpm wrote:
Sat Nov 06, 2021 11:52 am
Sling around your referral code, Grumble, it seems worth the £25 reservation fee.
Certainly, it’s https://rippleenergy.com/?ogu=2236
Looks like Ripple 2 is about to launch, if anyone wants to jump on board.
Thanks for the heads up. I’ve just signed up.

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Re: Solar Panels

Post by Grumble » Thu Feb 10, 2022 7:38 am

The way the Ripple offer is structured you get bigger savings the higher base price is, so it pays back quicker.
A bit churlish

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Re: Solar Panels

Post by Gfamily » Thu Feb 10, 2022 9:25 am

Grumble wrote:
Thu Feb 10, 2022 7:38 am
The way the Ripple offer is structured you get bigger savings the higher base price is, so it pays back quicker.
But, but, when fusion power comes in and electricity is too cheap to meterTM, the payback time will never come :shock:
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Re: Solar Panels

Post by lpm » Fri Feb 11, 2022 10:24 pm

Reserve by end of Sunday. Launch on Monday. One week for reservers, then open to general public until sold out.
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Re: Solar Panels

Post by bjn » Sat Feb 12, 2022 2:57 am

lpm wrote:
Fri Feb 11, 2022 10:24 pm
Reserve by end of Sunday. Launch on Monday. One week for reservers, then open to general public until sold out.
Going to buy as much as I can. Should see if I can do it through and ISA or SIPP, but I doubt it.

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Re: Solar Panels

Post by Gfamily » Sat Feb 12, 2022 3:18 am

bjn wrote:
Sat Feb 12, 2022 2:57 am
lpm wrote:
Fri Feb 11, 2022 10:24 pm
Reserve by end of Sunday. Launch on Monday. One week for reservers, then open to general public until sold out.
Going to buy as much as I can. Should see if I can do it through and ISA or SIPP, but I doubt it.
The principal means of return is via remittance against electricity costs through the supplier you agree to sign up for; so there are limits to the means of securing returns of your investment.
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Re: Solar Panels

Post by bjn » Sat Feb 12, 2022 8:43 am

I know. The cap is something like 3kW.

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Re: Solar Panels

Post by lpm » Mon Feb 14, 2022 10:24 am

Oh hello, it's going to be near to Trump's golf course place, I hope it's visible and makes him have a tantrum.

Not on top of a mountain but near the coast. Maybe the west coast of Scotland can get a few gentle breezes?

Upsized from 2 turbines to 8 - presumably shows big demand.

4.9% return over 25 years, based on their assumptions. Hmm. That's lower than I remember. Maybe I hadn't included the lag from paying now to getting savings from Nov 2023.

https://static.rippleenergy.com/assets/ ... eOffer.pdf
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Re: Solar Panels

Post by lpm » Mon Feb 14, 2022 10:47 am

Target is 14,400 members. I think the first one was about 2,000.
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Re: Solar Panels

Post by badger » Mon Feb 14, 2022 11:55 am

lpm wrote:
Mon Feb 14, 2022 10:47 am
Target is 14,400 members. I think the first one was about 2,000.
Now 14,399 members.

Right, now I need to get on with some more general investing in renewables. Oh, and insulate my house more effectively.

This continues to be a useful thread in a useful forum. Thanks all.

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Re: Solar Panels

Post by Imrael » Mon Feb 14, 2022 1:02 pm

I've just paid for my ripple energy allocation (reserved ages ago). No savings until end 2023 when the wind farm actually starts whirring. I eventually went for a little below my estimated consumption, since we're doing a bunch of insulation work that should bring it down.

they are a bit vague on over-generation (ir your shares pay for more than you use) - they say you dont lose it but imprecise on mechanism. I@m guessing it ends up as a surplus on your electricity account.

At the moment they are only dealing with Octopus as a supplier - I'm already with them and they do say others may come and you dont need to switch until end next year, but I guess that could be awkward for some people.

As far as I can see the only real problem is if I emigrate - the withdrawal terms are OKish I think. (When I die the shares are inheritable - sort of. Its a co-op membership but provisions to pass on to a beneficiary)

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