Solar ... In the news

QrizB

https://forums.moneysavingexpert.com/discussion/comment/81943045#Comment_81943045

I'm reminded of a similar discussion from 2022:

https://forums.moneysavingexpert.com/discussion/comment/79366781#Comment_79366781

Maybe we won't be going around this buoy again in 2030?

JKenH

https://forums.moneysavingexpert.com/discussion/comment/81943135#Comment_81943135

My experience of my ENE roof made me think that 60% was a bit generous so I put figures into PVGIS for a 4kW set up on a 39 degree pitch roof (like mine) in Lincolnshire and it suggested 3996 kWh (S) vs 1962 kWh (N). That’s less than 50%. The biggest difference is in winter when the N roof only generates 24 kWh compared to 141kWh south facing or 17%. Putting solar on a north facing roof will only work if there are decent export rates but as more and more solar is rolled out we can expect the value of summer midday generation to fall.

A shallower pitch of say 30% will give better results of 3942kWh vs 2249 kWh or 57%.

At the risk of being reported (again) by someone on here for quoting Google AI, typical roof slopes in the UK are

• Traditional/Victorian: 35°–45°+
• Modern Houses: 30°–35°
• Bungalows/Extensions: 20°–30°
• Low-Pitch/Garages: 10°–20°
• 


North facing solar would work reasonably well on bungalows or garages but not so well on traditional urban housing stock.

Netexporter

My roof is 25 degree pitch, and a bit east of north, which is where the figure lodged in my noggin from.

The main point being that we get get a huge dip in Agile prices in the middle of the day and we could do with more to satisfy the morning and evening peaks.

michaels

Problem with putting loads of solar on a new estate is you basically have a small power station so need the infrestructure to support this. My parents are not allowed to add to their 4kwp array because their local grid can't cope with any more power…..

NedS

https://forums.moneysavingexpert.com/discussion/comment/81943626#Comment_81943626

Indeed, and the developer should be footing the cost of upgrading the local network as part of the planning permissions. Or add in battery storage for later consumption to prevent saturating the local grid, which is probably the cheaper option for a developer, and certainly for the homeowner.

Magnitio

https://forums.moneysavingexpert.com/discussion/comment/81943281#Comment_81943281

New housing estates near where I live have lots of complex roofing to accomodate windows just to make the houses look more interesting. It makes it much more challenging to build and insulate and owners have used thermal imaging cameras to show the cold spots where it hasn't been done properly.

Not one of the housing estates has had solar from new. Heat pumps are being put in some of the houses, but one of these developments has had numerous issues due to the poor design and installation, with high bills as a result. Fortunately, the next development area being planned will have houses that are better insulated and have both solar and heat pumps.

QrizB

There's some terrible science reporting in the news at the moment.

Here's the story from The Independent (don't worry, lots of other outlets are just as wrong):

https://www.independent.co.uk/news/science/solar-panel-breakthrough-renewable-energy-japan-b2948851.html

If you take the article at face value, Japanese scientists have developed 130% efficient solar panels. It literally claims "an energy conversion efficiency of 130 per cent".

But that's not what they've done at all.

Here's the scientific journal article (paywalled, but the abstract is free).

https://pubs.acs.org/doi/10.1021/jacs.5c20500

The big breakthrough is that, when doing some clever photochemistry, they've persuaded a single photon to sometimes result in two excited molecules rather than one.

That's it. No direct reference to solar cells, panels, or electricity production.

I'm very happy for the scientists and hope their successful publication in the Journal of the American Chemical Society helps them when the next go to seek research funding, but it's not going to result in 130% efficient solar panels.

JKenH

This article sheds a bit more light on the research and its potential application in solar cells.

Scientists push solar cell efficiency to 130% using new impossible “spin-flip” system - PVBuzzMedia

• A new solar breakthrough may overcome a long-standing efficiency barrier. 
• Researchers used a “spin-flip” metal complex to capture and multiply energy from sunlight through singlet fission. 
• The result reached about 130% efficiency, meaning more energy carriers were produced than photons absorbed. This could lead to much more powerful solar panels in the future.

“This research introduces a new strategy for amplifying excitons, although it is still at the proof-of-concept stage. The team aims to integrate these materials into solid-state systems to improve energy transfer and move closer to practical solar cell applications.”