The Alternative Green Energy Thread

Exiled_Tyke

QrizB said:

JKenH said:

Good news of course but is it? The grid is struggling to cope with this level of solar in the middle of the day and day ahead prices are regularly going negative mid afternoon.

Cheap electricity in the middle of the day will be guzzled up by smart EV chargers. My Ohme has done this a couple of times this year; I've plugged in and have expected it to charge overnight, but instead Ohme and Octopus have chosen slots in the middle of the afternoon.

JKenH said:

But for how long can this be sustained without it impacting on our existing export rates. Flux is now below 10p daytime rate. I left Flux and moved to Agile Import and fixed (actually variable) Outgoing tariffs, the latter paying a flat 15p/kWh but I don’t see this being maintained throughout the summer.

I was expecting Fixed Outgoing to drop from 15p last year, and can't quite fathom why Octopus are still paying that much. They're overpaying significantly compared to commercial generation, as far as I can tell.

EON are even paying 16.5p!

It might cause problems for householders who have installed solar panels in the hope of a quick payback (potentially as few as 5 years) but the energy companies, Ofgem and UK Gov aren't responsible for your ROI calculations.

paul991 said:

Why is it not better to charge batteries  , heat waters , heat houses, and store energy in things like a Zeb /tepeo heater.

Self-consumption is the obvious answer to low or negative export prices. If you're not getting paid to export, you might as well use it to substitute for gas.

This is my experience too. Almost every day my car is now charging during the day with Octopus when I'm only plugging to get my PV excess into the car. To mitigate the effect  I've tethered the car back to charging at 60% (i.e. 4 1/2 kW) and have set the charing percentage to 10%.  

Surely in the longterm surely increased use of EV's, consumers learning to switch use to peak production times and large scale batteries will deal with the effect of over PV production. 

JKenH

Exiled_Tyke said:

QrizB said:

JKenH said:

Good news of course but is it? The grid is struggling to cope with this level of solar in the middle of the day and day ahead prices are regularly going negative mid afternoon.

Cheap electricity in the middle of the day will be guzzled up by smart EV chargers. My Ohme has done this a couple of times this year; I've plugged in and have expected it to charge overnight, but instead Ohme and Octopus have chosen slots in the middle of the afternoon.

JKenH said:

But for how long can this be sustained without it impacting on our existing export rates. Flux is now below 10p daytime rate. I left Flux and moved to Agile Import and fixed (actually variable) Outgoing tariffs, the latter paying a flat 15p/kWh but I don’t see this being maintained throughout the summer.

I was expecting Fixed Outgoing to drop from 15p last year, and can't quite fathom why Octopus are still paying that much. They're overpaying significantly compared to commercial generation, as far as I can tell.

EON are even paying 16.5p!

It might cause problems for householders who have installed solar panels in the hope of a quick payback (potentially as few as 5 years) but the energy companies, Ofgem and UK Gov aren't responsible for your ROI calculations.

paul991 said:

Why is it not better to charge batteries  , heat waters , heat houses, and store energy in things like a Zeb /tepeo heater.

Self-consumption is the obvious answer to low or negative export prices. If you're not getting paid to export, you might as well use it to substitute for gas.

This is my experience too. Almost every day my car is now charging during the day with Octopus when I'm only plugging to get my PV excess into the car. To mitigate the effect  I've tethered the car back to charging at 60% (i.e. 4 1/2 kW) and have set the charing percentage to 10%.  

Surely in the longterm surely increased use of EV's, consumers learning to switch use to peak production times and large scale batteries will deal with the effect of over PV production. 

I would presume you are on Intelligent Octopus Go, in which case is it not cheaper to charge overnight at 7p and export your surplus at 15p/kWh?

Peak solar production tends to coincide with the middle of the day when most people are working so, for the average working man/woman, switching use is not that easy. That is why the peak usage times are before and after the working day. As we electrify those peaks are likely to get bigger rather than smaller. Yes, heat pumps and hot water systems, once electrified can soak up some of the daytime solar excess but the expansion of grid scale solar is likely to outpace the growth of heat pumps and replacement of combi  boilers. 

On a personal level, with 350 litres of hot water storage capacity and 6kW of immersion heaters I can make some use of cheap/negatively priced electricity but not everyone is so lucky. If I only had 3kW of immersion heater capacity virtually any attempt to exploit cheap rates would mean I was using my export potential first and that has a real cost of 15p/kWh rather than the enticing cheap/negative rates we see on Agile. My son has an EV and V2G but can’t access cheap daytime rates as he is at work on weekdays and like most people has a combi boiler. 

Where electrification works is in countries with significant quantities of hydro electricity and that is not the UK. We need more dispatchable generation and batteries ahead of any further expansion of grid scale solar. Yes, more solar generation reduces CO2 but at a huge cost. I suppose it depends on priorities and at the moment policy dictates CO2 saving is more beneficial than cost saving. Will that change as the chickens come home to roost?

JKenH

Mayor reveals schools receiving green scheme money

The mayor has revealed which London schools will benefit from his £2.9m Greener Schools programme, which aims to install solar panels, heat pumps and other technology across the capital.

A total of 38 schools in 16 boroughs will receive funding through the pilot, with councils contributing an extra £9.6m to the project, according to the Local Democracy Reporting Service.

City Hall said it believed the scheme could save schools an average of almost £15,000 on their energy bills as a result of the measures, which also include insulation and LED lighting.

https://www.bbc.co.uk/news/articles/cvgn4pewq4lo

i hope I have got my maths right. 

Cost - The Mayor puts in £2.9m and council £9.6m - total £12.5m.
Benefit - 38 schools x £15k pa savings = £570k pa

22 years to repay capital if interest free.

If interest rates 4% then interest pa is £500k. Net benefit £70k pa. Ignoring compounding capital repaid after 178 years.

Life of panels - 30 years? Heat pump 20 years?

Good investment? Maybe the Mayor is expecting energy costs to rise.

michaels

I bet the savings all come from led lighting....

paul991

Apart from the Heat pumps all the other work would need to be done anyway.ie  Lighting upgrades , window replacements and insulation .Part of the problem being money for routine maintenance of public buildings is hard to come by but Lump sums for upgrades are available .

QrizB

paul991 said:

Part of the problem being money for routine maintenance of public buildings is hard to come by but Lump sums for upgrades are available .

CAPEX is glamorous, OPEX isn't.

Few politicians have ever wanted to be photographed cutting a ribbon in front of a completed round of preventative maintenance.

JKenH

April Fool piece in New Scientist or genuine? 

Wind farm developers are worried about neighbours stealing their wind

“Wake effects are nothing new. It’s been there since the very beginning of wind farm development,” says Sheikh. “What has changed over the last few years has been the rapid scale of the growth in the size of wind turbines.” 

Estimates of the financial impact of wake losses vary. Research published last year by a team at the University of Bergen in Norway suggests wind farm wakes can extend up to 50 kilometres and cut wind resources available to downstream farms by as much as 20 per cent. Other estimates from researchers in the US suggest wakes could affect yields by more than 30 per cent in certain severe conditions.

In the meantime, firms with sites already in development or under construction are battling it out in the planning and legal systems to protect their wind resources. Some are establishing “wind wake agreements” that might include compensation for affected wind farms, as well as agreements to design new sites to minimise downstream impacts.

https://www.newscientist.com/article/2475172-wind-farm-developers-are-worried-about-neighbours-stealing-their-wind/

Maybe it is real.

https://www.sciencedirect.com/science/article/pii/S0308597X2300430X

edit: while reading around Icame across this article. I do subscribe so can’t access the full article but the headline is interesting. Lots of money in this for lawyers, no doubt. 

Ørsted and Equinor predict up to £361m in wake losses from North Sea wind farm plans

Ørsted and Equinor have estimated that wake effects caused by the planned 1.5GW Outer Dowsing offshore wind farm in the North Sea could result in combined losses of up to £361 million (€422 million) for their existing projects. 

https://www.windpowermonthly.com/article/1914480/orsted-equinor-predict-361m-wake-losses-north-sea-wind-farm-plans

1961Nick

JKenH said:

I know I keep harping on about the number of solar farms in our area but I recently came across this map showing the extent of solar farms in the Trent Valley. Newark in the bottom left corner of the map will be completely surrounded by solar farms. 9% of the Newark parliamentary constituency is scheduled to be covered by solar farms connected to existing HV lines which were previously powered by three coal fired stations at West Burton, Cottam and High Marnham. Strategically the location is perfect but this is all good quality agricultural land in the Trent Valley.

That's a lot of lost food production that will presumably have to be replaced with imports? I'm familiar with some of the villages in those areas & the views will change from open countryside to a sea of black as far as the eye can see in all directions. 

paul991

How lucky you are we just get builders building new houses that locals can not afford

JKenH

paul991 said:

How lucky you are we just get builders building new houses that locals can not afford

Oh, well, it’s better to look out on aspirational houses than affordable housing.