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To approve or not approve that is this week's question.


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Well next week I will pop along to the local consultation event for UK's largest solar farm which will be just down the road from Whitstable in Graveney. It will have 350MW, 4 x the current largest, at peak output and spread over 890 acres. I know what I think - what do you think?

 

Loads on the Web - neatly balanced description HERE from the Guardian.  

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I'll just chuck a few facts and views in for fun.

 

The very best plants can convert around 7% to 9% of the energy from the sun into usable energy, as biomass, oil etc, per unit ground area.  Most struggle to get better than about 5%.

 

A poor solar farm might convert 15% of the energy from the sun over that area into electricity, a good solar farm might convert 18% to 20%.

 

The price of solar panels and the associated kit is now cheap enough that there are no subsidies needed for commercial solar farms, and they still generate electricity at a lower price than many other forms of power generation.

 

As a final point, solar farms can still grow some plants around them, and even graze sheep on the land, so all told solar farms are still very much a positive in terms of the productivity of the land.  Whether people like the look of them is another point.  Personally, I'd rather see a field of solar panels than a field of oil seed rape, but that may be because I hate the smell of oil seed rape..............

 

 

Edited by JSHarris
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You may find that the modules they buy are larger than are normally fitted on domestic installations.

 

Much of the profitability is down to how they are selling the power, but they would not be doing it without a decent rate of return.

There are more than just FiTs (and I think this is too large for that scheme anyway) for selling electricity.

 

The issue about growing a few crops and grazing sheep is a bit of a sop to 'greenies and nimbys' they have a surprising amount in common.  The last thing that a solar farm operator wants is a sheep nibbling though a 1000V DC cable.  Weed killer usually sorts out the grass growth.

 

You could ask them why they are not building some agricultural/light industrial units under some of the modules.  A few thousand square metres of single story units could come in handy and give a secondary income to help the impoverished economy.  Tattoo artists and nail bars are popular.  As are tanning salons.

 

If you want a bit of fun, ask what grade the land was and how many kWh of food energy it can produce a year (about 0.25 kWh.m-2 if they are lucky, and that is before inputs).

Also ask if there is any coal in that area, Kent is a coal area after all.

You could also point out that when I lived in Kent, I was taken to Whitstable in 1973/4 and shown the sea frozen over.  Has that happened recently?

You could also point out that 350MW peak power should produce about 375 TWh/year.  If Hinkley was up and running at full power, it would produce about 7140 TWh/year.

If Hinkley takes another 19 years to be built, it will still be behind this PV farm on production (I think Hinkley got the nod 11 years ago and it wont be ready on time, and then our government can get out of the contract).

Or, you could point out that during the summer, it will produce about 0.3% of the nations power, in winter about 0.03% (check those numbers as they seem low and my eyesight is failing).

 

 

Edited by SteamyTea
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1 hour ago, JSHarris said:

The very best plants can convert around 7% to 9% of the energy from the sun into usable energy, as biomass, oil etc, per unit ground area.  Most struggle to get better than about 5%.

 

Whilst I am quite happy to see fields of solar panels, I would say that the benefit of the other two are that they can be stored for use later. I think the reality is a need for an energy mix - solar, wind, tidal, nuclear.

 

Edit - I do wonder if the reason they can do it without fits, as well as lower panel prices, are that they know electricity prices will be increasing over the next 5 years or so. The figures agreed for Hinckley point would also suggest this.

Edited by Trw144
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If you decided to burn all the biomass that the world produces, and that includes the oceans, it would last around 400 days with the worlds current primary energy usage.

Not a lot of 'storage' really.

Be a bit smokey as well.

 

But yes, there does need to be a mix, but we are nowhere near even starting on replacing fossil fuel globally, so now is not the time to stop project because of something that may be a problem in 25 years time (going to take us at least that long to build a new nuclear power station).

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19 minutes ago, SteamyTea said:

If you decided to burn all the biomass that the world produces, and that includes the oceans, it would last around 400 days with the worlds current primary energy usage.

Not a lot of 'storage' really.

Be a bit smokey as well.

 

 

No, but then solar panels can't produce vegetable oil either and, whilst they could power a deep fat fryer, you d potentially be lacking both the potato and oil to fry it in.

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8 hours ago, Trw144 said:

No, but then solar panels can't produce vegetable oil either and, whilst they could power a deep fat fryer, you d potentially be lacking both the potato and oil to fry it in.

Loose / Loose - but only beans are grown on this land it is grade 3b agricultural apparently!

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8 hours ago, CC45 said:

Starving people will replace the panels with food crops eventually.......

Maybe not - nitrogenous fertilizers are critical to high food yields, and they require energy to produce. If you're out of fossil fuels, that means the next best source may well be solar. Turning the energy from a solar farm on marginal agricultural land into nitrates which are then used on far better land will give you more food than ripping up the solar panels and growing without the nitrates.

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Back when I was a chemist for a short time, one of the experiments I had to look after (overnight) was measuring the CO2 uptake of hemp, being grown in a sealed chamber, under artificial light.  We were using C14O2 in the "air"" mixture in the sealed chamber, so we could measure the uptake rate by simply taking small leaf samples (via an airlock hatch) periodically and measuring the C14 to get a good indicator of CO2 uptake rate over time.  As almost all all the carbon in plants comes from the CO2 they extract from the atmosphere, this was a reasonable way to measure conversion efficiency.  Hemp was used because it's a fast growing commercial crop (or was still back in the 1970's, when we were doing this) that supposedly had a fairly high conversion ratio.  IIRC, we measured a conversion efficiency of a bit under 3%.

 

Take away the energy used in producing fertilisers, pesticides, harvesting, processing and transport and I strongly suspect that the efficiency would be barely more than about 1%.

 

The key to solving our energy problems lies not in inventing new forms of generation, in the main (although a fusion generator would be nice) but in inventing efficient long-term energy storage.  The best we can do at the moment, in terms of whole life cost, is probably pumped water storage, like Dinorwic, but there are so few locations that lend themselves to pumped storage that it's not really a practical solution.  It'll be interesting to see how the new Tesla battery system in South Australia works.  The main problem I think is that it's likely to only have a relatively short life, ten to fifteen years maybe, and the storage capacity is pretty small.

 

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Why can't the government fit a pair of pv panels on every uk home / building ?

The DNO's can be made to reinforce the grid out of their 'marginal' profits and that gargantuan area of m2 of wasted space will be utilised to reduce / slow down the destroying of the planet on which we've selfishly decided to suck dry at any cost. 

Wouldn't that be a better way to spend the money being tossed into the nuclear pot?

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1 hour ago, JSHarris said:

I strongly suspect that the efficiency would be barely more than about 1%.

And that was in a lab, just about ideal growing conditions.

1 hour ago, Nickfromwales said:

Why can't the government fit a pair of pv panels on every uk home / building ?

At that sort of level there would probably not be a need to reinforce the grid and it would, in effect, work as daytime storage.

Trouble is that it is very costly.  It is not the cost of the modules.  A roof time is pretty cheap, getting it changed is pretty expensive (if done properly and legally, not some pikey up a ladder).

 

I think we run the risk of just going over what Dr MacKay said a decade ago:

https://www.withouthotair.com/download.html

A quick, slightly out of context, quote:

 

"Energy crops as a coal substitute

If we grow in Britain energy crops such as willow, miscanthus, or poplar
(which have an average power of 0.5 W per square metre of land), then
shove them in a 40%-efficient power station, the resulting power per unit
area is 0.2 W/m2. If one eighth of Britain (500 m2 per person) were covered
in these plantations, the resulting power would be 2.5 kWh/d per person."

 

There is also no lack of land suitable for agriculture, just look at a picture:

 

 

Great Britain.jpg

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2 minutes ago, PeterW said:

That’s similar @Nickfromwales to the million solar roofs project that was kicked off under Clinton in the US. The issue is usually one of legislation and people getting on a band wagon rather than financing - just look at MCS...!

I mean government driven and non negotiable. Set installation costs and no room for pickpockets. The councils could take on the task of installation and maintenance or have we forgotten such simple tasks don't actually NEED to be subbed out all the bloody time?

By the time 3rd party pickpockets ( who invariably do the shittest quality lowest integrity work which ultimately creates maintenance and reliability issues & their subsequent rectification costs ) get a slice of the pie it'll be at least a decade before any benefit is felt. 

Its something that should be a not for profit drive, managed by the government and undertaken at cost. It would also create some jobs for life. 

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2 hours ago, Nickfromwales said:

managed by the government and undertaken at cost

We are currently seeing just how fantastic this government is at negotiating a deal.

If you really wanted to do this, then you need to get the companies that stand to gain the most, so the DNO/Power Generation companies.

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1 hour ago, SteamyTea said:

We are currently seeing just how fantastic this government is at negotiating a deal.

If you really wanted to do this, then you need to get the companies that stand to gain the most, so the DNO/Power Generation companies.

I know it's wishful thinking that our own internal infrastructure could manage this without it costing unnecessary £b of taxpayers cash. 

Ho hum. ??

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9 hours ago, Nickfromwales said:

I mean government driven and non negotiable. Set installation costs and no room for pickpockets. The councils could take on the task of installation and maintenance or have we forgotten such simple tasks don't actually NEED to be subbed out all the bloody time?

By the time 3rd party pickpockets ( who invariably do the shittest quality lowest integrity work which ultimately creates maintenance and reliability issues & their subsequent rectification costs ) get a slice of the pie it'll be at least a decade before any benefit is felt. 

Its something that should be a not for profit drive, managed by the government and undertaken at cost. It would also create some jobs for life. 

 

Great idea, but where would you find all those people from who would want to do it for the right reasons? Neither government or councils can manage even the simplest of tasks, never mind something of this scale!

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9 minutes ago, Roger440 said:

 

Great idea, but where would you find all those people from who would want to do it for the right reasons? Neither government or councils can manage even the simplest of tasks, never mind something of this scale!

Time for change, as you can only blame the management. What a shambles of an office we have running the country. 

Selflessness and integrity are not any of the 'qualities' residing behind the doors of no.10. 

My biggest worry is how much worse it'll get. :/

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