Green, ethical, energy issues in the news

Martyn1981

Bit of a digression, so apologies, but I thought it might be worth posting this news item as it deals with the issue of protein crop production v's meat farming (so this is from the AGW side, rather than direct green energy).

I found it interesting as the source is a actually a nuisance, so removed (harvested?) already:

Protein from gorse bushes could feed millions of people, says expert

The gorse bushes that have invaded many Scottish landscapes could produce enough protein to feed millions of people, according to the leader of a Scottish government research programme.

The surprising suggestion by Prof Wendy Russell, at the University of Aberdeen, comes from research on the protein content of invasive plants that have to be doused with herbicides or burned back to keep them under control.

Gorse contains 17% protein and broom has 21% protein, she said, adding: “Gorse and broom were fed to cattle at times when crops failed in the past, so we think protein from these types of plants could be used as animal food. If protein isolates are produced in the correct way, so to be safe, they could be considered as human food in the future.”

“The whole point about gorse is it is actively being removed from marginal lands – it’s something we can gain protein from at no extra cost,” she said. “We have a huge amount of gorse all over Scotland and when we did the calculations, just by active removal from marginal land, there’s enough gorse protein to easily feed [Scotland’s] population.”

Scotland has little arable land, which is why Russell examined invasive plants on marginal land. “When you make a protein isolate from gorse, 57% of the total leaf protein can be recovered at up to 95% purity,” she said. “We’re using about 4.5 to 6kg of CO2 to produce [a kilogram of] isolate, compared to an average for meat of 102kg of CO2.”

And as a 'twofer', I read this para:

Fifteen Scottish farmers also planted hemp this year for the first time, Russell said. “They’re really concerned about the climate and want to do their best. They really are optimistic about the commercial viability of the crop and its climate credentials.”

and as I've been interested in hemp for quite a long time, since it can produce so many products, bio-degrable materials, grows at an astonishing speed (up to 2 harvests pa), and can be used to produce bio-fuels, or even just pellet based biomass, I found a recent article looking at it:

The UK countryside is ablaze with hemp farms. But how do they help the climate?

Despite the lack of state support, more and more farmers in the UK are turning to hemp production for its economic and environmental benefits. It's legal for them to sell a variety of hemp-made products, like milk and seed powers, to supermarkets and other businesses.

In the right conditions, hemp absorbs more CO2 than it takes to cultivate - sequestering nine to 15 tonnes of CO2 per hectare. That’s almost twice as much as a forest of the same size, according to a Cambridge University researcher. Could it be the next big carbon sucker?

NigeWick

Protein from gorse bushes could feed millions of people, says expert

It looks as though lab grown meat will be the protein of the future. I honestly can't see gorse "feeding millions of people."

Hemp:- I think growing and using hemp is a good idea. Clothing, cordage, ropes and building materials for starters.

michaels

Undersea pumped storage co-located with wind farms
Will this ‘ocean battery’ buried in the seabed be an offshore wind game changer? (electrek.co)

Which made me want to look up the round trip efficiencies of different storage technologies and I found this link, not sure how accurate the values are:
Fact Sheet | Energy Storage (2019) | White Papers | EESI

	Max Power Rating (MW)	Discharge time	Max cycles or lifetime	Energy density (watt-hour per liter)	Efficiency
Pumped hydro	3,000	4h – 16h	30 – 60 years	0.2 – 2	70 – 85%
Compressed air	1,000	2h – 30h	20 – 40 years	2 – 6	40 – 70%
Molten salt (thermal)	150	hours	30 years	70 – 210	80 – 90%
Li-ion battery	100	1 min – 8h	1,000 – 10,000	200 – 400	85 – 95%
Lead-acid battery	100	1 min – 8h	6 – 40 years	50 – 80	80 – 90%
Flow battery	100	hours	12,000 – 14,000	20 – 70	60 – 85%
Hydrogen	100	mins – week	5 – 30 years	600 (at 200bar)	25 – 45%
Flywheel	20	secs - mins	20,000 – 100,000	20 – 80	70 – 95%
Characteristics of selected energy storage systems (source: The World Energy Council)

Martyn1981

Chers, that's a great list. The biggest takeaway for me is how it seems to support all of the negativity I keep reading in articles and comments about hydrogen as a form of large scale leccy storage.

I've generally been quite bullish about H2, accepting the low efficiency, on the grounds that vast amounts can be stored relatively easily. But with my very limited knowledge on the technicalities and issues, it seems to me that H2 storage requires similar technologies, techniques, and even locations as CAES. So if CAES is more efficient* then does this leave room for H2, given that more stages are involved in H2 storage?

*CAES was the only figure that jumped out at me on that list, as 70% seemed too high, but the paper explains that this is with thermal storage of heat too. I believe LAES can be around 50-80% efficient, but again requires waste heat or cold for the higher figures, and can't be stored as simply as CAES and H2. I think LAES sits somewhere between intraday and longer term storage.


I'm rambling now, but another potential source of storage for the UK (and other countries in Europe) could be PHS in Norway. Currently they have little PHS, they don't need it since they have vast hydro storage. At present, if UK leccy is in excess and cheap enough then Norway may buy it and 'store' it in the form of dialing down their own hydro generation. But I believe there have been studies that around 20GW of storage/supply could be opened up in Norway by the addition of pumped hydro and catchment lagoons at existing hydro sites. This is a project and level of investment that Europe, rather than just Norway, might want to consider. I think this may have been mentioned a decade or so back as part of the Desertec idea, where Norway's main role/contribution would be hydro generation and being a large European battery.

michaels

Martyn1981 said:

Chers, that's a great list. The biggest takeaway for me is how it seems to support all of the negativity I keep reading in articles and comments about hydrogen as a form of large scale leccy storage.

I've generally been quite bullish about H2, accepting the low efficiency, on the grounds that vast amounts can be stored relatively easily. But with my very limited knowledge on the technicalities and issues, it seems to me that H2 storage requires similar technologies, techniques, and even locations as CAES. So if CAES is more efficient* then does this leave room for H2, given that more stages are involved in H2 storage?

*CAES was the only figure that jumped out at me on that list, as 70% seemed too high, but the paper explains that this is with thermal storage of heat too. I believe LAES can be around 50-80% efficient, but again requires waste heat or cold for the higher figures, and can't be stored as simply as CAES and H2. I think LAES sits somewhere between intraday and longer term storage.


I'm rambling now, but another potential source of storage for the UK (and other countries in Europe) could be PHS in Norway. Currently they have little PHS, they don't need it since they have vast hydro storage. At present, if UK leccy is in excess and cheap enough then Norway may buy it and 'store' it in the form of dialing down their own hydro generation. But I believe there have been studies that around 20GW of storage/supply could be opened up in Norway by the addition of pumped hydro and catchment lagoons at existing hydro sites. This is a project and level of investment that Europe, rather than just Norway, might want to consider. I think this may have been mentioned a decade or so back as part of the Desertec idea, where Norway's main role/contribution would be hydro generation and being a large European battery.

I guess li-ion and h2 have the advantage that they can be used to transport stored energy and used in a mobile context.

Also h2 may be somewhat compatible with the existing natural gas infrastructure and of use in some high temperature industrial processes.

However in terms of a simple stationary storage solution I would have to agree with you.

Coastalwatch

Has anyone else signed up to Co Charger, either as a Host or Chargee which enables those with no off road parking, to charge up safely/regularly and within walking distance of their home. If so, how has it worked for you?

https://co-charger.com/

Verdigris

No, but it is something I'm intending to investigate, because I'll have a lot of solar surplus in the summer, if my plans go as intended.

Coastalwatch

Well, I didn't see this one coming! Another take on hydro coupled with excess Solar or Wind with scalable storage to cover short and long term needs. No rare earth minerals or materials required with a round trip efficiency of 78% and lifetime expectation of two decades but more likely three to five! I couldn't really understand the written explanation but the accompanying video just confirms that a picture is worth several hundred words!

Utility scale ocean battery, a bedfellow for floating PV

Dutch start-up Ocean Grazer grabbed the limelight at the Consumer Electronics Show (CES 2022) in Las Vegas last week, where its new design for an offshore energy storage system based on hydro dam technology garnered the “Best of Innovation” award.

The Ocean Battery is a pumped hydro system in a box. Buried in the seabed, the battery provides storage up to the gigawatt-hour scale by connecting rigid reservoir elements, each with a storage volume of 10MWh. The system can be adapted to various forms of renewable power generation such as floating PV, offshore wind, tidal and wave energy.

 

https://www.pv-magazine.com/2022/01/12/utility-scale-ocean-battery-a-bedfellow-for-floating-pv/

Coastalwatch

Afraid I'm unable to fathom precisely how the finances are worked out here, but there are some eye watering figures stated. Not sure how far £39m will go towards compensating the remaining utilities, I suspect not far.

Recently I was aware of one of the CEO's, I believe from SSE, complaining about the Green levy applied to bills but said nothing about the sums of wholesale energy prices which contributed more than double this figure. He conveniently forgot to mention that Utilities receive full payment from customers for each and every kWh exported from all PV array's and distributed locally which costs them nothing to generate. This figure will remain unknown until Smart Meters are installed with every array and the total published.

CfD portfolio to pay back to electricity suppliers amid high wholesale prices

With high wholesale prices alongside lowered levy rates, electricity suppliers are to receive reconciliation payments for their Contracts for Difference (CfD) contributions for the first time.

While generators receive top-up payments to the strike price they are paid for the electricity they generate, but they can also pay back money when the market prices rise beyond their strike price, with the scheme therefore providing both revenue certainty for generators alongside acting as a hedge for consumers.

In this instance, the expected net payments from generators over the quarter totalled £133,667,990, while the TRA for Q4 2021 was £208,986,765. Meanwhile, the TRA for Q1 2022 is set at £303,432,348, and is netted off against the Q4 2021 numbers, which means the LCCC is forecasting a total reconciliation payment of £39,222,407.

https://www.solarpowerportal.co.uk/news/cfd_portfolio_to_pay_back_to_electricity_suppliers_amid_high_wholesale_pric

QrizB

Thanks for sharing the CfD article, I've been following the Levy Dashboard at https://www.lowcarboncontracts.uk/dashboards/cfd/levy-dashboards for a few months now.

It's fascinating to see how high wholesale FF prices mean the CfD-funded renewables are currently not "expensive" and may act as a (small) stabilising factor on energy bills.