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Since no one has said it this time (someone usually does). Welcome to this forum Peter Z.
And here's a suggestion, for some of the more established members of the community.
How about actually listening to what new posters have to say, before deciding they haven't got anything useful to contribute. Why not give folk the benefit of the doubt, a few posts to get started.
As I have said before people get put off contributing if they receive a brutal reception. Politeness cost nothing and are one of the core rules of this website.
Lets face it, without new contributors the conversation in this room will become pretty stale. And I personally log on here to learn something new.
Thank you for the warm welcome.
Just to add, I'm also here to learn and to listen to different points of view. If everyone agreeed with me then there would be little point in having a discussion. I get the impression some of the established members do like to throw their weight around a little, but they are easily knocked down to size
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Hi NangHi John
Sorry I have to admit, I didn't really get that one either. I think a little more context might add some clarity.
I think that John was referring to the assumption made for simultaneous household demand. If, at a point in time, every household (~24million) turned on a 3kW kettle the total demand would be ~72GW for kettles alone, so with a UK generation capacity of around 80GW combined with kettles not being the only demand source there would be problems.
The grid and total generating capacity is designed to cope with average demand with a safety tolerance, not maximum possible demand.
HTH
Z"We are what we repeatedly do, excellence then is not an act, but a habit. " ...... Aristotle
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Hi Nang
I think that John was referring to the assumption made for simultaneous household demand. If, at a point in time, every household (~24million) turned on a 3kW kettle the total demand would be ~72GW for kettles alone, so with a UK generation capacity of around 80GW combined with kettles not being the only demand source there would be problems.
The grid and total generating capacity is designed to cope with average demand with a safety tolerance, not maximum possible demand.
HTH
Z
I was really thinking about what is called "the local loop" in the telephone business. The area where the pylons get stepped down from very high voltage 3 phase and then to single phase. It is designed on the assumption that this local group of consumers will only be taking 1 - 2 kW on average.
So If we have got lots of nuclear power to absorb during the night, the logical way to do it is to install heat pumps (especially if the properties are not on the gas grid) and gear up the power by say 3 to one and store it in the floor slabs of the "Ecoised" (new word invented here) properties, while qualifying for RHI (renewable heat incentive)
Ok now it is time to switch on: Bang - we have just blown up the local transformer.
At current rates of improvement to our grid - which is lagging behind parts of the Continent - it could take 50 years to arrive at the above model.
Larger domestic properties could need three phase supply to efficiently run a heat pump.
Perhaps we could get some advice from Denmark - having missed out on the chance to squander a North Sea bonanza, they have managed to create an economy that is far less energy dependent than ours.
HOW DID THEY DO IT?
There is a useful collection of statistics here: http://www.energy.eu/#dependency
Energy consumption by EU-member states, their net imports and dependence rate in 2008.
The most important suppliers of crude oil and natural gas were Russia (33% of oil imports and 40% of gas imports) and Norway (16% and 23% respectively).
EU Member State - Gross Energy Consumption - Net imports - Energy Dependency
Cyprus - 2.6 - 3 - 100%
UK - 229.5 - 49.3 - 21.3%
Denmark - 20.9 - (8.1) - (36.8%)
Gross energy consumption in Million tonnes oil equivalent (Mtoe). (production plus imports, less exports).
Net imports means imports minus exports.
% is imports divided by gross consumption.
Denmark is a net exporter of energy.0 -
John_Pierpoint wrote: »I was really thinking about what is called "the local loop" in the telephone business. The area where the pylons get stepped down from very high voltage 3 phase and then to single phase. It is designed on the assumption that this local group of consumers will only be taking 1 - 2 kW on average.
So If we have got lots of nuclear power to absorb during the night, the logical way to do it is to install heat pumps (especially if the properties are not on the gas grid) and gear up the power by say 3 to one and store it in the floor slabs of the "Ecoised" (new word invented here) properties, while qualifying for RHI (renewable heat incentive)
Ok now it is time to switch on: Bang - we have just blown up the local transformer.
At current rates of improvement to our grid - which is lagging behind parts of the Continent - it could take 50 years to arrive at the above model.
Larger domestic properties could need three phase supply to efficiently run a heat pump.
Perhaps we could get some advice from Denmark - having missed out on the chance to squander a North Sea bonanza, they have managed to create an economy that is far less energy dependent than ours.
HOW DID THEY DO IT?
There is a useful collection of statistics here: http://www.energy.eu/#dependency
Energy consumption by EU-member states, their net imports and dependence rate in 2008.
The most important suppliers of crude oil and natural gas were Russia (33% of oil imports and 40% of gas imports) and Norway (16% and 23% respectively).
EU Member State - Gross Energy Consumption - Net imports - Energy Dependency
Cyprus - 2.6 - 3 - 100%
UK - 229.5 - 49.3 - 21.3%
Denmark - 20.9 - (8.1) - (36.8%)
Gross energy consumption in Million tonnes oil equivalent (Mtoe). (production plus imports, less exports).
Net imports means imports minus exports.
% is imports divided by gross consumption.
Denmark is a net exporter of energy.
Thanks for clarifying John
Just to make sure I get this, heat pump turns elect into heat energy right?
So this approach is a bit like economy 7 then, take the power off peak when the (nuclear / coal fired stations are producing it anyway) and use it to heat the slabs under the houses. Release the heat during peak times to reduce the demands on the grid?
I guess the process would lead to a more even loading on the grid, thoughout the day. Yes?Follow the progress of 7 domestic arrays at :- http://www.uksolarcasestudy.co.uk/0 -
John_Pierpoint wrote: »Perhaps we could get some advice from Denmark - having missed out on the chance to squander a North Sea bonanza, they have managed to create an economy that is far less energy dependent than ours.
HOW DID THEY DO IT?
There is a useful collection of statistics here: http://www.energy.eu/#dependency
Energy consumption by EU-member states, their net imports and dependence rate in 2008.
The most important suppliers of crude oil and natural gas were Russia (33% of oil imports and 40% of gas imports) and Norway (16% and 23% respectively).
EU Member State - Gross Energy Consumption - Net imports - Energy Dependency
Cyprus - 2.6 - 3 - 100%
UK - 229.5 - 49.3 - 21.3%
Denmark - 20.9 - (8.1) - (36.8%)
Gross energy consumption in Million tonnes oil equivalent (Mtoe). (production plus imports, less exports).
Net imports means imports minus exports.
% is imports divided by gross consumption.
Denmark is a net exporter of energy.
Hi John - I hope we don't take any advice from Denmark on how to generate our electricity.
There are many differences between Denmark and the UK. They are blessed with vast hydro natural resources ideal of electricity generation for their small population. They have also ammassed a massive wind resource too, enabled by the hydro resources (which give them cheap primary reserve to balance the intermittancy of the wind, something we don't have and have to simulate with Dinorwig).
The result of all this is that they have the most expensive electricity in the developed world, and at times, an uncontrollable supply. Yes they export a lot, but that isn't by choice. They sometimes have negative export prices, and always very low export prices. The gainers are their neighbouring countries who are paid sometimes to take their excess. It does seem counterintuitive to us that excerss generation can be a problem - but that's exactly what it is for Denmark at times (when domestic demand is low and wind generation high). Of course there are many theoretical solutions to the excess generation, but putting them into practice so they don't have to occasionally pay others to take it, has so far eluded them.
There was a paper written on the Danish electricity industry and the self-imposed problems of it a few months ago, I'll try to find a reference to it.
As a general point, when other countries require consultancy of electricity networks, it's usually our ngc who are turned to for advice - it's one area where we are still aknowledged as world leaders.0 -
grahamc2003 wrote: »Hi John - I hope we don't take any advice from Denmark on how to generate our electricity.
There are many differences between Denmark and the UK. They are blessed with vast hydro natural resources ideal of electricity generation for their small population. They have also ammassed a massive wind resource too, enabled by the hydro resources (which give them cheap primary reserve to balance the intermittancy of the wind, something we don't have and have to simulate with Dinorwig).
The result of all this is that they have the most expensive electricity in the developed world, and at times, an uncontrollable supply. Yes they export a lot, but that isn't by choice. They sometimes have negative export prices, and always very low export prices. The gainers are their neighbouring countries who are paid sometimes to take their excess. It does seem counterintuitive to us that excerss generation can be a problem - but that's exactly what it is for Denmark at times (when domestic demand is low and wind generation high). Of course there are many theoretical solutions to the excess generation, but putting them into practice so they don't have to occasionally pay others to take it, has so far eluded them.
There was a paper written on the Danish electricity industry and the self-imposed problems of it a few months ago, I'll try to find a reference to it.
As a general point, when other countries require consultancy of electricity networks, it's usually our ngc who are turned to for advice - it's one area where we are still aknowledged as world leaders.
I read this with interest
In all the discussions it always feels like all the issues of the generating methods of the future, come down to an inability to store electricity so it can be used at an appropriate time.
I found this article on Wikipedai:-
http://en.wikipedia.org/wiki/Grid_energy_storage
It feels like the viability of grid storage comes down to economics.Generally speaking, energy storage is economical when the marginal cost of electricity varies more than the costs of storing and retrieving the energy plus the price of energy lost in the process.
You think that Denmark would be investing heavily in various grid storage technology to try to prevent them from having the issues you described.
If they became the world leaders in this area you would think that other countries would be buying their expertise for years to come, as we all gear to using more renewables.Follow the progress of 7 domestic arrays at :- http://www.uksolarcasestudy.co.uk/0 -
I read this with interest
In all the discussions it always feels like all the issues of the generating methods of the future, come down to an inability to store electricity so it can be used at an appropriate time.
I found this article on Wikipedai:-
http://en.wikipedia.org/wiki/Grid_energy_storage
It feels like the viability of grid storage comes down to economics.
You think that Denmark would be investing heavily in various grid storage technology to try to prevent them from having the issues you described.
If they became the world leaders in this area you would think that other countries would be buying their expertise for years to come, as we all gear to using more renewables.
Storing energy on the scale required is the holy grail of electricity generation. No one has found a cheap way of doing it. The cegb designed and built Dinorwig which stores energy by pumping water from a lower lake to a higher lake, then releasing it when required. To do that required a mega cost - it was at the time and for a while after, the most expensive civil engineering endeavour in the World. That cost was not justified (as you will often read) by storing cheap electricity and releasing it at high prices, but by supplying primary/secondary reserve - i.e. the ability to generate with a few seconds notice when the frequency of the grid falls (which can happen at any time, not just at peaks). After its reserve duty, then as a secondary duty, it will sell any spare capacity beyond that required for reserve for the remaining part of the day at peak rates. It need not have actually generated anything at all to actually pay for itself very quickly via supplying this reserve duty (a kind of insurance, only called upon if the frequency drops). Before Dinorwig, this reserve was supplied by conventional stations operating away from their most efficient in order to have this frequency support ability, at a very high cost.
The reasons we simply don't throw up lots more pumped storage is firstly the cost and suitable topography unavailable. Currently, there is sufficient reserve capacity within the grid, but in the future as more intermittent power is added (wind, and to a very much less extent solar), more will be required This extra cost of the extra reserve due to intermittent generation is very rarely taken into account in the costs of any intermittent generation.0 -
UK pumped storage schemesgrahamc2003 wrote: »Storing energy on the scale required is the holy grail of electricity generation. No one has found a cheap way of doing it. The cegb designed and built Dinorwig which stores energy by pumping water from a lower lake to a higher lake, then releasing it when required. To do that required a mega cost - it was at the time and for a while after, the most expensive civil engineering endeavour in the World. That cost was not justified (as you will often read) by storing cheap electricity and releasing it at high prices, but by supplying primary/secondary reserve - i.e. the ability to generate with a few seconds notice when the frequency of the grid falls (which can happen at any time, not just at peaks). After its reserve duty, then as a secondary duty, it will sell any spare capacity beyond that required for reserve for the remaining part of the day at peak rates. It need not have actually generated anything at all to actually pay for itself very quickly via supplying this reserve duty (a kind of insurance, only called upon if the frequency drops). Before Dinorwig, this reserve was supplied by conventional stations operating away from their most efficient in order to have this frequency support ability, at a very high cost.
The reasons we simply don't throw up lots more pumped storage is firstly the cost and suitable topography unavailable. Currently, there is sufficient reserve capacity within the grid, but in the future as more intermittent power is added (wind, and to a very much less extent solar), more will be required This extra cost of the extra reserve due to intermittent generation is very rarely taken into account in the costs of any intermittent generation.- Ben Cruachan, Scotland (1965), 440 MW
- Foyers, Scotland (1975), 300 MW (2 x 150 MW units)
- Dinorwig, Wales (1984), 1728 MW (6 x 288 MW units)
- Ffestiniog, Wales (1963), 360 MW (4 x 90 MW units)
Ferrybridge C (where A1 crosses the river Aire) eventually took me on.
At the time the workers could disappear over a weekend, because some other site was offering an extra shilling an hour (5p).
Loch Awe, as we knew the first on this list, was one such alternative site.Thanks for clarifying John
Just to make sure I get this, heat pump turns elect into heat energy right?
Yes, but with an uplift called the COP (Coefficient of performance) There is a lot of BS and creative accounting but the COP should normally be 3 - 4 ie put in one unit of electricity and get 3 or 4 units of heat. Unfortunately the best COP's are achieved when the heat gradient is least. So outside temperature 7 degrees inside temperature of underfloor heating 35 degrees gives a good COP, but outside temperature -10 and inside temperature +35 gives less COP just when you need more heat. (Solution: strike a match and light the log burner)
As floor slabs take a long time to heat up and cool down (a bit like a nuclear power station) you cannot simple turn it on and off like gas central heating. Works best if left to run constantly, especially at night, pumping just hard enough to maintain the required internal temperature of the well insulated property. The equipment has "heuristics" - simplest version is monitoring the outside and starting to pump hard before the temperature drop gets anywhere near the internal thermostat. In theory could be linked to tomorrow's temperature and sunshine forecast.
So if you have a gas boiler capable of producing 25 kW, you would still need a hear pump with a potential electrical input (say) 10kW.
Pretty obviously the grid could not cope locally if a whole neighbourhood tried to switch on one sub zero winter night.grahamc2003 wrote: »Hi John - I hope we don't take any advice from Denmark on how to generate our electricity.
There are many differences between Denmark and the UK. They are blessed with vast hydro natural resources ideal of electricity generation for their small population. They have also ammassed a massive wind resource too.
I agree, it is probably "over" investment in wind energy and the exports are caused by using the German grid as a vast battery.
Denmark is almost as flat as Holland - the hydro is in that rich petro economy Norway that uses almost none of its oil for space heating.
Both countries have lots of heat pumps installed, especially where gas is not available.0 -
In addition to the above steps on Generation, there is a far greater emphasis on centrally managing consumption.
I posted earlier that on my place in the USA I am offered a small cash incentive to allow my Aircon/heating and water heater to be switched off remotely for no more than 30? minutes. Restricting consumption much as they are doing in Japan at the moment.
It would be very easy to 'save' huge amounts of power to buy time until, say, a gas turbine got up to speed.0 -
grahamc2003 wrote: »Hi John - I hope we don't take any advice from Denmark on how to generate our electricity.
There are many differences between Denmark and the UK. They are blessed with vast hydro natural resources ideal of electricity generation for their small population. They have also ammassed a massive wind resource too, enabled by the hydro resources (which give them cheap primary reserve to balance the intermittancy of the wind, something we don't have and have to simulate with Dinorwig).
The result of all this is that they have the most expensive electricity in the developed world, and at times, an uncontrollable supply. Yes they export a lot, but that isn't by choice. They sometimes have negative export prices, and always very low export prices. The gainers are their neighbouring countries who are paid sometimes to take their excess. It does seem counterintuitive to us that excerss generation can be a problem - but that's exactly what it is for Denmark at times (when domestic demand is low and wind generation high). Of course there are many theoretical solutions to the excess generation, but putting them into practice so they don't have to occasionally pay others to take it, has so far eluded them.
There was a paper written on the Danish electricity industry and the self-imposed problems of it a few months ago, I'll try to find a reference to it.
As a general point, when other countries require consultancy of electricity networks, it's usually our ngc who are turned to for advice - it's one area where we are still aknowledged as world leaders.
Very interesting insight into how other countries work, thanks for this.
As oil prices rise I think the Danes will be pleased of the investment they have made, I wish we could see similiar investment here in the UK. In the 5-10 years that surplus electricity could well be soaked up by electric cars.
Anyone got any views or insights into the idea of a European supergrid?0
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