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Smart Energy Usage


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#21 SteamyTea

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Posted 05 March 2016 - 01:37 PM

View PostDamonHD, on 05 March 2016 - 11:35 AM, said:

Turning off all the UK's fridges and freezers for a short while if the grid was in trouble (or at peak demand times) would save about 2GW, likewise for heating circulation pumps another 1GW.
10 [W] x 50x106 [fridges] = 0.5GW.
or about 1% off the demand at 6pm yesterday.

Yesterday is a good example as we have a cold snap and it is dark at 6pm and is a time of peak demand, so the type of scenario where load shedding is needed.

I like the idea of a small PV unit (say 500Wp, 1 micro-inverter) to take the load of this kind of thing. Could even be wall mounted to reduce installation costs. 50/50 split East/West.

Edit:

Had a look at what happened yesterday, if we could have lopped half a gig of consumption, it would have made very little difference.
I also don't think that there was enough shift in the frequency to make any load shedding kick in, only a 0.08 Hz varianceAttached File  Grid Demand.jpg   33.37K   2 downloads.

Edited by SteamyTea, 05 March 2016 - 01:53 PM.


#22 DamonHD

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Posted 05 March 2016 - 01:46 PM

Typical fridge/freezer is ~1kWh/d or 40W average, x >25 million households is 1GW, but peaks of double that, ie instantaneous savings of 2GW.

Rgds

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#23 SteamyTea

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Posted 05 March 2016 - 01:58 PM

Possibly with old fridges, but newer ones, like my 100 quid one I bought last year, run on virtually nothing, bit like new laptops and light bulbs.
It would probably be easier to have a fridge trade-in scheme than change the infrastructure to turn fridges off.

It is the big loads that need to be reduced, why I suggested showers.
Limiting kettles to 2.5 kW and training people to fill them less would have a bigger impact.
Trouble is if you tell people to half fill a kettle, they will fill it up to the brim out of bloody mindedness.
So maybe kettles should have a mass sensor and a clock in them that stops them boiling if they are more than half full. :D

#24 DamonHD

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Posted 05 March 2016 - 02:19 PM

Just putting a smaller element in would train people to put less water in.

I found it difficult to get a <3kW kettle that would also just boil one cup of water at a time.

We have a business idea to resolve that, but are too busy to deal with it at the moment.

But in any case ST please do not mix up the almost orthogonal goods of *using less* and *shifting when it's used*. Both need to happen, and may be independent.

Rgds

Damon

Edited by DamonHD, 05 March 2016 - 02:22 PM.


#25 SteamyTea

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Posted 05 March 2016 - 02:41 PM

My ten quid Tesco kettle is a nominal 3kW and boils one mug's worth, and often does.
Not sure how it would survive in a hard water area.

Edited by SteamyTea, 05 March 2016 - 02:43 PM.


#26 PeterStarck

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Posted 05 March 2016 - 04:01 PM

View PostAlphonsox, on 05 March 2016 - 12:10 PM, said:

You will effectively agree to "lend" power to the grid from your car batteries which will be replenished overnight when demand falls.

Isn't discharging and recharging the batteries frequently going to have a detrimental and therefore costly effect for the owners. Would that be compensated for in some way? What happens when you want to use the car but the energy company has taken all your juice?

#27 SteamyTea

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Posted 05 March 2016 - 04:14 PM

There is also the cost of upgrading the grid to allow enough cars to be charged and discharged,
I think, as I have mentioned elsewhere on here and over on the other place, that small, local, independent storage is possibly the easiest and cheapest way to do it.
I would rather have the DNO fit, service and pay for a kWh of storage by my meter box, than have to do it myself.

Edited by SteamyTea, 05 March 2016 - 04:21 PM.


#28 DamonHD

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Posted 05 March 2016 - 04:19 PM

View PostPeterStarck, on 05 March 2016 - 04:01 PM, said:

Isn't discharging and recharging the batteries frequently going to have a detrimental and therefore costly effect for the owners. Would that be compensated for in some way? What happens when you want to use the car but the energy company has taken all your juice?

These are common questions, answered years ago on various "V2G" sites.

Firstly, you'd be paid enough to cover the wear-and-tear costs else you wouldn't do it.

Secondly, you'd put a limit on how far your battery could be discharged, else you wouldn't do it.

Let's avoid DM-style hyperventilation here at least!

Rgds

Damon

#29 SteamyTea

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Posted 05 March 2016 - 04:25 PM

I hate to say it, but at the moment (who knows what the future holds), V2G is rather a self serving concept to justify having electric cars.
Don't get me wrong, they will happen and be useful one day, just as some sort of decent storage system will be available, just that day is not in the foreseeable future.
If we want to cut CO2e emissions now, which is really what we need to be doing, we have to use proven and affordable technology.
So it goes back to the basics of insulate, airthighness and simple management.

Edited by SteamyTea, 05 March 2016 - 04:26 PM.


#30 DamonHD

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Posted 05 March 2016 - 04:50 PM

All of that is true ST, and I still don't see myself owning a car, whatever its power source.

But, storage is going to be key one way or another. As Ed Davey said very recently, cheap mass storage would make most of the rest of our knotty energy problems go away, pretty much.

So, I'm going to put in a SunampPV (I hope), knowing that it will nominally put UP my CO2e a little, but getting back some of that exergy by carefully timing when I let it top up from the PV on my roof, eg by reducing what I spill to the grid at solar noon.

Rgds

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#31 PeterStarck

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Posted 06 March 2016 - 08:29 AM

View PostDamonHD, on 05 March 2016 - 04:19 PM, said:

These are common questions, answered years ago on various "V2G" sites.

Firstly, you'd be paid enough to cover the wear-and-tear costs else you wouldn't do it.

Secondly, you'd put a limit on how far your battery could be discharged, else you wouldn't do it.

Let's avoid DM-style hyperventilation here at least!

Rgds

Damon

It was a genuine question to which I didn't know the answer. It would be good if there was a choice, but I don't see how anyone knows yet how it would work.

#32 SteamyTea

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Posted 06 March 2016 - 08:50 AM

Peter
The usual way that these type of things are modelled is through thought experiment games.
So take the scenario of Vehicle to Grid energy swapping, what would normally happen is that you create different scenarios and then ask people to put a 'price' on different aspects of them. Then look at the data and see what comes out.

One scenario may be:
Allow up to 40% discharge, limiting the range of the vehicle to 60 miles.
Then you ask one group of people how much they want to be paid for that, and ask another group how much they would have to pay to use an alternative if they had to (say they need the car to do more than 60 miles).
With large enough sampling they two figures should match.

Generally what happens is that these sorts of surveys are biased from the beginning.
So another survey would offer 3 different payments to allow the DNO to discharge your car, but offer no alternative method of transport.
Another could offer you 'free' public transport in return for discharging.

Sampling bias is the biggest problem, this happens a lot when they do surveys to 'value nature'. They do a lot of them down here via the nearby university. These surveys often happen at my nearby park. The trouble is that the respondents are a self selected group by the very act of being where the questions are being asked about.

So if we did a survey on here about V2G we would get very different answers and some people would have to be excluded from the start, no vehicle owners, people with no alternatives (that is Damon and myself out, Damon don't want a car and there are no alternatives for me to get home from work).

This is a major problem when trying to establish if an idea would actually work. Especially true when there are cultural and geographical differences.

Edited by joiner, 06 March 2016 - 09:01 AM.


#33 PeterStarck

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Posted 06 March 2016 - 04:37 PM

Steamy, so at this stage it's just pie in the sky. We don't even know if there will be enough electric cars to enable such a scheme, there may be a significant advance in hydrogen powered cars for instance. I won't hold my breath then for simple cheap mass electrical storage, just concentrate on reducing usage.

#34 SteamyTea

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Posted 06 March 2016 - 05:00 PM

I am of the view that there will not be much market penetration of EVs, and especially ones that are capable of V2G, in the next 10 years.
It took 25 years for diesels to go from about 12% of the EU market to about 50% (Cames, Helmers 2013)
I could well be wrong and someone has already got a small, lightweight battery pack all ready to go into a vehicle, but even if that is the case, we do not have the infrastructure to support EVs.
We also don't have a government that is willing to support them (new EVs are going to attract road duty soon).
What will probably happen is that gasoline hybrids will replace diesels in the next ten years.

Edited by SteamyTea, 06 March 2016 - 05:00 PM.


#35 Alphonsox

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Posted 09 March 2016 - 01:51 PM

Looks like Nissan France are trialing V2G

http://www.dailymail...ing-energy.html