MikeSharp01 Posted September 21, 2023 Share Posted September 21, 2023 10 minutes ago, SteamyTea said: As for EVs, if you buy a Tesla, it is almost certainly made in China. They make good cars now. Using quite a lot of coal. Link to comment Share on other sites More sharing options...
SteamyTea Posted September 21, 2023 Author Share Posted September 21, 2023 Just now, MikeSharp01 said: Using quite a lot of coal. I don't know the grid intensity for China. Doubt anyone does. Probably worth splitting the country up as it is physically a large place. Then see what the industrial areas use. Link to comment Share on other sites More sharing options...
saveasteading Posted September 21, 2023 Share Posted September 21, 2023 55 minutes ago, Mr Blobby said: For every GW of wind capacity there needs to be a GW of conventional thermal plant for when the wind doesn't blow. No. They can build enormous battery packs to store the surplus. I quoted for a couple of projects which would be sophisticated warehouses, jam-packed with redundant car batteries (ie after replacement). I was way down the supply chain and had to sign secrecy papers, and i doubt they were built...but maybe some were. I think they were to be adjacent to gas power stations to use off-peak capacity, but could better be connected to wind source. More conventionally, they can currently use surplus power to recharge reservoirs at the hydro power stations that have pump storage. On a much smaller scale, we could have smart metering in times of surplus, and we heat our floor slabs then, thus storing energy (but useful as heat only). Link to comment Share on other sites More sharing options...
SteamyTea Posted September 21, 2023 Author Share Posted September 21, 2023 There had just been a bit on PM about EV quotas not being changed in the UK. So by 2030, any brand of car has to sell 80% EVs. Think they said next year it is 22%, but may have misheard that as was driving. So while we will be able to get an ICE up to 2035, they may be impossible to actually buy. I wonder if that was forgotten, or done on purpose. Link to comment Share on other sites More sharing options...
SteamyTea Posted September 21, 2023 Author Share Posted September 21, 2023 (edited) 1 hour ago, SteamyTea said: don't know the grid intensity for China Just had a quick Google and it seems to be 531 g/kWh in 2022. High, but no worse than we were a decade ago. "The leading sources of China’s emissions are the power sector (48% of CO2 emissions from energy and industrial processes), industry (36%), transport (8%) and buildings (5%)" https://www.iea.org/reports/an-energy-sector-roadmap-to-carbon-neutrality-in-china/executive-summary Edited September 21, 2023 by SteamyTea Link to comment Share on other sites More sharing options...
Mr Blobby Posted September 21, 2023 Share Posted September 21, 2023 1 hour ago, SteamyTea said: Not really so. Installed capacity is not the same as generation, RE generated differently from FF, i.e. you cannot schedule up to the Betz's Limit for a windturbine, but you can for a hydro (usually), gas or nuclear. This means they are integrated into the national grid differently. Demand side management can take up a lot of the slack. 2 decades ago there was a few studies done showing that anything more than 25% RE would cause grid stability, we now frequently hit close to 60% RE penetration. While it is still early days for demand side management, storage is moving ahead. So it may be fairer to say that for every MW of RE name plate capacity, we would need a MWh of storage (or whatever the numbers say we need). As for EVs, if you buy a Tesla, it is almost certainly made in China. They make good cars now. Yes capacity is not the same as generation. Here in Ireland the move to renewables is years ahead of GB, admittedly for a smaller system, but also the political will is stronger and less NIMBYism about onshore wind. Northern Ireland is decoupled from the GB national Grid because the single all Island market was set up as part of the good Friday agreement. The Irish grid has a target of 75% renewables. No nuclear here so mostly wind. Currently at about 50% wind generation. Above that yes demand management is key to grid stability. There is still however thermal plant available to step in here when the wind doesn't blow. I've seen no evidence of storage moving ahead. It is not technically or financially possible for battery storage to take up the slack and replace GWs of thermal plant. As far as I have seen batteries are used for frequency stability and, very rarely, a few seconds of reserve. There would need to be a massive step change in technology and cost for batteries to play any significant role in energy supply when the wind doesn't blow. As you say, demand management will play an increasing role for instant response, but mostly it's gas turbines in the UK that step in when the wind doesn't blow. But that's ok I think because most of the time the wind does blow. 1 Link to comment Share on other sites More sharing options...
Mr Blobby Posted September 21, 2023 Share Posted September 21, 2023 27 minutes ago, saveasteading said: No. They can build enormous battery packs to store the surplus. I quoted for a couple of projects which would be sophisticated warehouses, jam-packed with redundant car batteries (ie after replacement). I was way down the supply chain and had to sign secrecy papers, and i doubt they were built...but maybe some were. I think they were to be adjacent to gas power stations to use off-peak capacity, but could better be connected to wind source. More conventionally, they can currently use surplus power to recharge reservoirs at the hydro power stations that have pump storage. On a much smaller scale, we could have smart metering in times of surplus, and we heat our floor slabs then, thus storing energy (but useful as heat only). Used for frequency response. Attached to existing power stations because they have the connection to the grid. They sit at 50% charge level all the time, discharging, charging a little. Link to comment Share on other sites More sharing options...
Mike Posted September 27, 2023 Share Posted September 27, 2023 On 21/09/2023 at 09:36, joe90 said: Yesterday I drove through Bristol where row after row of terraced houses exists where charging at home is impossible and even parking outside your home is impossible, how are these people going to use EV,s Perhaps by using a car with swappable batteries. Or, in an urban area like Bristol, by joining a car share scheme, rather than owning a car. Link to comment Share on other sites More sharing options...
Onoff Posted September 28, 2023 Share Posted September 28, 2023 On 20/09/2023 at 20:48, nod said: I did say this quite a while back Gas boilers on new builds next Watch this space What if you don't have mains gas, LPG? Link to comment Share on other sites More sharing options...
nod Posted September 28, 2023 Share Posted September 28, 2023 I can’t remember ever working on a housing site that doesn’t have mains gas I suppose if there’s so many units they can go to great lengths to get gas on site Our friends self built two years ago and went for LPG over HP and bitterly regret it now Link to comment Share on other sites More sharing options...
ToughButterCup Posted September 28, 2023 Share Posted September 28, 2023 44 minutes ago, nod said: I can’t remember ever working on a housing site that doesn’t have mains gas ... Townie. Link to comment Share on other sites More sharing options...
Onoff Posted September 28, 2023 Share Posted September 28, 2023 8 minutes ago, ToughButterCup said: Townie. No main drainage, pavements or streetlights here either. Link to comment Share on other sites More sharing options...
SteamyTea Posted September 28, 2023 Author Share Posted September 28, 2023 11 minutes ago, Onoff said: No main drainage, pavements or streetlights here either. But we still have childhood diseases, and pitchforks. Link to comment Share on other sites More sharing options...
Marvin Posted September 28, 2023 Share Posted September 28, 2023 On 21/09/2023 at 06:22, nod said: Until they make a HP cheaper to run than gas Most homes will rely on gas boilers or oil Hi @nod You are right. but I think of it in terms of until gas becomes more expensive and therefore HPs are cheaper to run.... Also peoples lifetime habits ( and the UK's housing stock!!!) needs to change away from burning hot radiators, windy and uninsulated homes, towards a low heat requirement with airtightness and better insulation. Either that or we learn to wear knitted jumpers again... Link to comment Share on other sites More sharing options...
Marvin Posted September 28, 2023 Share Posted September 28, 2023 1 hour ago, nod said: I can’t remember ever working on a housing site that doesn’t have mains gas I suppose if there’s so many units they can go to great lengths to get gas on site Our friends self built two years ago and went for LPG over HP and bitterly regret it now We have no mains gas so we ran our renovated home on LPG for about 3 years which was fine (remember it's well insulated and airtight home) but we then grouped technology together with an ASHP, PV and solar power diverter which has worked out to be the most efficient. LPG was about £600 a year including hot water. ASHP is about 1600kW a year excluding hot water ( well about 80% is via the PV diverter). Link to comment Share on other sites More sharing options...
SteamyTea Posted September 28, 2023 Author Share Posted September 28, 2023 5 minutes ago, Marvin said: well about 80% is via the PV diverter That is quite impressive. How much PV you got, and how much extra would you need to get it to 99% Thinking about what @JohnMo did with his 'winter solar fence'. Link to comment Share on other sites More sharing options...
JohnMo Posted September 28, 2023 Share Posted September 28, 2023 I think with battery, my utilisation has jumped to about 99.ish percent. Today I kicked the ASHP in to heating mode and set the house thermostat slightly high for the PV production period. Not sure I need the heating on, but it's just about free due to PV and starts to heat the floor up slowly after summer UFH cooling. So combining dumping heat into 60T of concrete (my floor) and when heat pump in an off cycle, any excess goes to battery. 3 hours ago, Marvin said: 1600kW a year As @SteamyTea missed your mistake, I will correct it, 1600kWh not kW, as in energy usage not power. 1 Link to comment Share on other sites More sharing options...
Marvin Posted September 28, 2023 Share Posted September 28, 2023 (edited) 3 hours ago, SteamyTea said: That is quite impressive. How much PV you got, and how much extra would you need to get it to 99% Thinking about what @JohnMo did with his 'winter solar fence'. Hi @SteamyTea Nice idea but... during the winter, with our 5.12kW array, some days we produce less than 1kWh the whole day. On December 11th 2022 the tally was 1.2kWh, however as the diverter only diverts unused energy and we use about 2-300 watts per hour during the day this resulted in nothing going into the hot water heating. However on the 12th Dec we produced 7.4kWh and on the 7th of December 13.94kWh. However on the 3rd December 0.41kWh. My rambling point is that heating the hot tank in the winter higher than 60C means we can make it last about 3 days. 99% of 365 days is - call it 4 days: Our entire plot surface area is too small to accommodate enough panels to supply enough power for heating the water for 361 days in the year. Edited September 28, 2023 by Marvin added an h to the kWs Link to comment Share on other sites More sharing options...
ToughButterCup Posted September 28, 2023 Share Posted September 28, 2023 3 hours ago, Marvin said: ... ASHP is about 1600kW a year ... I have a spare Tin Hat if you need one.....😑 2 Link to comment Share on other sites More sharing options...
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