Solar ... In the news

Martyn1981

Slightly different 'solar' news from the usual:

Recycling heat for a ‘385% efficient’ solar desalinator

MIT scientists have developed a solar desalinator which transports heat from the sun through a ten-stage process of evaporation and condensation. The group estimates a $100 device employing their innovation could provide the daily drinking water needs of a family.

Martyn1981

Carbon Commentary newsletter extract(s):

1, India solar plus storage. The world’s largest auction for bids to supply electricity with guaranteed availability for at least six hours a day concluded in India. The two winning bids in the auction for 1.2 GW of solar capacity combined with commitments to supply at least 3.0 GWh a days in peak times were at around 6 US cents per kilowatt hour, a price that comfortably beats supply from most coal-fired power stations in India. 

9, Solar. The head of ENEL Green Power said that the cost of worldwide solar was now typically ‘well below $40 a MWh’. In the best locations, such as Chile, the figure is as low as $20. These numbers are lower than can achieved by gas or coal in a new power station. Adding storage to the typical project adds no more than 15%, he said, bringing the average location up to around $45. (He didn’t specify how much storage that estimate included). 

silverwhistle

https://www.theguardian.com/environment/2020/feb/18/researchers-claim-solar-efficiency-breakthrough-for-flexible-skin

Martyn1981

silverwhistle said:

https://www.theguardian.com/environment/2020/feb/18/researchers-claim-solar-efficiency-breakthrough-for-flexible-skin

Obviously I need to be a bit careful mentioning coatings or cladding as I don't want to appear distasteful, but cheap and light wall mounted solar would be ideal for tall buildings and flats, at least for those  with E, S and W facing walls. Annually I think vertical PV works out at around 80% of pitched PV.

Martyn1981

Low bids for German PV auction with an average of 5.2cents/kWh but a lowest bid of 3.55c/kWh. Certainly shows the potential of UK PV (similar generation and therefore economics to Germany) if it was allowed back into the CfD auction scheme, possibly/probably net zero subsidy. [Note German (most European) auctions don't include the infrastructure costs of grid connection, so UK prices are typically a bit higher, perhaps £ to € straight conversion.]

German PV tender delivers record low solar power price of €0.0355/kWh

Germany’s Federal Network Agency, the Bundesnetzagentur, has announced 18 solar projects with a combined generation capacity of 100.6 MW were allocated in the latest tender held for PV projects ranging in size from 750 kW to 10 MW.
The tender was almost five times oversubscribed as the agency fielded proposals for 493 MW of project capacity.
The lowest winning bid accepted for the solar power to be generated by the new facilities was €0.0355/kWh ($0.038315) – a German record. The highest successful bid was for €0.0521.
Average price
The average final price in the procurement round was €0.0501/kWh, significantly less than the €0.0568 average delivered by the previous tender of the same kind, in December. The latest average tariff did not, however, better the €0.0490/kWh tendered by the bidders in October.

michaels

Martyn1981 said:

Low bids for German PV auction with an average of 5.2cents/kWh but a lowest bid of 3.55c/kWh. Certainly shows the potential of UK PV (similar generation and therefore economics to Germany) if it was allowed back into the CfD auction scheme, possibly/probably net zero subsidy. [Note German (most European) auctions don't include the infrastructure costs of grid connection, so UK prices are typically a bit higher, perhaps £ to € straight conversion.]

German PV tender delivers record low solar power price of €0.0355/kWh

Germany’s Federal Network Agency, the Bundesnetzagentur, has announced 18 solar projects with a combined generation capacity of 100.6 MW were allocated in the latest tender held for PV projects ranging in size from 750 kW to 10 MW.
The tender was almost five times oversubscribed as the agency fielded proposals for 493 MW of project capacity.
The lowest winning bid accepted for the solar power to be generated by the new facilities was €0.0355/kWh ($0.038315) – a German record. The highest successful bid was for €0.0521.
Average price
The average final price in the procurement round was €0.0501/kWh, significantly less than the €0.0568 average delivered by the previous tender of the same kind, in December. The latest average tariff did not, however, better the €0.0490/kWh tendered by the bidders in October.

I think we need to be careful in assuming that a CFD strike price below the average unit price in the market means a zero subsidy.  If all the generation takes place at times when prices are low (typical in Germany for solar) then there may stil be a net subsidy even when the strike price is at the average generation price.

Martyn1981

michaels said:

I think we need to be careful in assuming that a CFD strike price below the average unit price in the market means a zero subsidy.  If all the generation takes place at times when prices are low (typical in Germany for solar) then there may stil be a net subsidy even when the strike price is at the average generation price.

Several problems with that argument, one, depends how low the CfD is compared to the average strike price, two, no way whatsoever will all PV generation take place at times when prices are low, and lastly, even if there is a subsidy top up (and related to point one) that would still be reflected in our bills with cost savings (low purchase price of those units) v's small subsidy top up. In fact even if the whole CfD came out of the LCF pot it would still reflect a low price for the leccy (low CfD contract), to explain, let's say the leccy was sold for £0, and the companies got the whole £45/MWh(?) CfD payment via top up, via the green energy fund, we as consumers would still 'only' be paying 4.5p/kWh for the leccy (before additional costs).

I really don't get the fear of cheap leccy at times, that's simply part of the move to intermittent RE, especially large capacities of wind generation. We know that there will be peaks and troughs, and that storage of many kinds will be needed. In the case of PV we might see contracts that favour E or W facing PV. My PV in the summer can generate more than household baseloads from 6.30am to 9pm. If all of that period is 'when prices are low' then that seems like something to celebrate, not fear. And of course most, if not all PV generation in the bottom 6 months (around 1/3rd of annual PV generation will not be when prices are necessarily low.

Martyn1981

For those who might be a bit confused by the PV / subsidy posts, it might be worth some explanation, ponderings and discussion.
Probably about 3yrs+ ago 'cells' posted that the PV industry would be self destroying as it grew, since it would flood supply at times, thereby reducing prices, income and profitability.
In a simplistic World, that would/could be true, assuming no outside factors, and the willingness of ever more PV deployment by self destructive PV companies.

In a World however, where PV costs keep falling, orientation and pitch are considered, demand for leccy grows, demand for daytime leccy grows (BEV's plugged in whilst folk are in work), and general storage of other forms, are deployed, we can safely assume(?) that PV will grow sensibly with one eye on profitability.

Moving on to subsidies and CfD's, these would remove any profitability concerns by establishing a minimum price for the leccy, via the 'top up to strike price' mechanism. But could mean too much PV generation at times - but only if said CfD contracts were too generous and more importantly too expansive, assuming a 'World' where we keep on issuing such contracts long after supply peaks become a concern (would we?)

Back to reality, and the CfD mechanism. Let's use an example just for clarity. Let's say that the CfD is issued at £40/MWh, and the average selling price is £50/MWh. Let's also assume that in all scenarios the companies enter a CfD as this gives them price certainty, and reduced funding costs (reduced risk factor for lenders).

Scenario 1. Prices are always £50/MWh, so the companies within the £40/MWh CfD contracts sell all leccy at £50/MWh, and hand £10/MWh into the CfD subsidy fund pot.

Scenario 2. Prices vary, but on average the leccy is sold at £50/MWh. Some times the companies will receive a subsidy (sold at less than £40/MWh), some times the companies will pay excess back into the subsidy pot (sold at more than £40/MWh), and the net effect will be that the subsidy pot gets £10/MWh for all sales.

Scenario 3. And now we are moving into reality. Prices vary, but it's safe to assume that the bulk of daytime generation in the better 4-6 months of the year will be delivered at roughly the same time (even assuming national distribution of PV and weather). This will of course depress prices during these peak times, but by how much? How much real (and artificial (attractive BEV charge rates)) demand will be created to offset this, how much will subsidy top ups at low prices be offset by subsidy repayments during low PV generation periods and/or high demand such as Summer evening peak sales, and low wind Winter daytimes, how much will that £10/MWh margin between average sales prices and the CfD strike price cover this, how will government CfD's both size and bid cap prices alter over time to address this concern as PV capacity grows, for example let's say a max bid cap of £35/MWh, or £30/MWh as the years roll on.

So whilst I accept that in theory there could be a problem with oversupply, or net subsidy payments*, I'd suggest that the market, PV companies, and the government will adapt to take all factors into account, and it's entirely possible for PV CfD's to be net subsidy zero (or better!).

*As explained before, and only my personal opinion, but if we rolled out loads of PV generation, and at say £40/MWh CfD it ended up receiving some subsidies, then that doesn't concern me at all, as it will still be a very cheap way to displace even more FF generation from the grid.

Exiled_Tyke

"Probably about 3yrs+ ago 'cells' posted that the PV industry would be self destroying as it grew, since it would flood supply at times, thereby reducing prices, income and profitability.
In a simplistic World, that would/could be true, assuming no outside factors, and the willingness of ever more PV deployment by self destructive PV companies."

I too think this is a non-argument to add to your comments: Industries don't fail because they get so cheap as to price themselves out of a market. In a competitive market with elastic demand they find an equilibrium.  Admittedly it may be that price is zero at peak production and low demand (for now). So there needs to be enough demand at times when PV produces (at a decent rate).  The concerns therefore (in my mind would be) -
1. Is PV more expensive than alternatives in which case it would disappear? The answer must surely be 'No'.  The starting point to this was that PV is getting cheaper. In addition the alternatives need to be cheaper at the same times of day as PV. The biggest competitor must surely be Wind which as we all know tends to complement PV nicely with a (generally) negative correlation of production to PV.  Other (less green) sources will continue to be priced out as governments continue to penalise them for their externalities. 

2. How big is the 'low demand' window? I'm guessing this will get increasingly smaller. As Martyn points out, EV charging and storage will continue to grow. In addition, how significant will the affect of consumers changing their habits be? I'm guessing this has a long way to go too. We've only just seen the beginning of industries having their usage 'tampered' with by energy providers to meet with the peaks and troughs of demand: those of us with domestic PV have adjusted (usually quite easily) to putting our high energy appliances on at times of highest production and technology must surely develop further to help with this? My system of matching demand with supply is to quite simply use the time-delay settings on my appliances (others use diverters to heat water when there is  excess electricity)  but surely more sophisticated aids will be developed in a relatively short time.  

Martyn1981

Exiled_Tyke said:

 The concerns therefore (in my mind would be) -
1. Is PV more expensive than alternatives in which case it would disappear? The answer must surely be 'No'.  The starting point to this was that PV is getting cheaper. In addition the alternatives need to be cheaper at the same times of day as PV. The biggest competitor must surely be Wind which as we all know tends to complement PV nicely with a (generally) negative correlation of production to PV.  Other (less green) sources will continue to be priced out as governments continue to penalise them for their externalities. 

Running with this, I'd certainly agree, looks like PV generation in the UK is competitive with wind, certainly competitive with wind in the summer and during daylight. So costs on a horses for courses basis seem fine and costs continue to fall, but ..... there's more ..... come on you knew that the super optimistic always has more to say ...... so .....

We also need to consider Perovskite PV, which is closing in on Silicon for efficiency, but is very, very cheap, and best of all, there is silicon/perovskite PV which should lift 'average' efficiencies from ~20% today to ~30% but for the same cost per Wp. That changes everything after a quick thunk - it means that for the same land, labour, transportation, racking etc etc a PV site will be able to install 50% more Wp, and whilst the PV cost will go up 50%, the other costs won't, though of course some cabling and inverter costs will rise to cope with higher throughput. With PV representing about 50% of the PV farm costs, that means a cost increase of ~25% for a generation increase of ~50%.

Still haven't finished, whilst ~30% efficiency looks do-able and lab generation is already there, silicon/perovskite might get closer to 40% in the medium to long term. Nice!

How Low Can Solar Cells Go? Perovskite Researchers Say Down, Down, Down

The cost of solar power is sinking practically by the day, and the next new “hot” solar cell material — perovskite — will push costs down even more. So far you can’t get perovskite solar cells in stores but this year will bring a trickle into the market, and a batch of new research suggests that the trickle will become a flood. When that happens, look out. The thermal coal market is already in the toaster and perovskite could fry it to a crisp while also dragging natural gas down along, too.

 A Market-Ready Perovskite Cell From Panasonic

Meanwhile, Panasonic and NEDO (Japan’s New Energy and Industrial Technology Development Organization) have been working on bringing manufacturing costs down for perovskite solar cell modules.

In the latest development, the collaboration has resulted in a 16.09% efficient PV cell that can be fabricated by deploying a high volume, high throughput process similar to inkjet printing.

Aside from bringing down costs, the lightweight cell can operate efficiently in applications where silicon solar cells are impractical, such as windows and building facades.

A conversion efficiency of 16.09% is pretty decent for that type of cell, but the partners plan on tweaking their perovskite formula for future improvements. In any case, the lower efficiency is balanced out by the potential for covering larger areas at less expense.

Perovskite & Silicon Together

On the higher end of the efficiency scale is the strategy of combining perovskite with silicon in a single tandem solar cell. The latest development on that score comes from a research team at the Kaunas University of Technology, in Lithuania.
Their new perovskite-silicon tandem cell has been Fraunhofer-certified at 29.15% efficiency, a record-breaker for that type of cell.