Nuclear power : how visions change

cells

kinger101 wrote: »

UK demand varies between 25GW and 60GW, so it's hard to even eliminate 50% of carbon without finding a way to somehow stabilize this demand fluctuation. This will need to be done by either grid storage, or demand manipulation.

uk peak is below 60GW now and the peak is continually falling as LEDs replace less efficient lighting

For nuclear the UK could install 30GW and operate them at almost full capacity with a little load following at night.

That means 30GW of nuclear 40GW of average demand = nearly 75% of all our needs

Electric cars also would make nuclear more viable more so than wind power. Smart cars connected to the grid charged at night would increase the low points and not add to the peaks.

So a 75% nuclear 25% gas infrastructure is possible and its proven to work on national scales


also the French actually use a portion of their nuclear fleet for heating industry and homes. Its why they use so much less nat gas and more electricity than us (even accounting for the nat gas used by UK generators)

cells

Garethgrew wrote: »

Solar is now cheaper per GW than, nuclear, why we don't go over to clean renewable I don't know. Seriously why.?

because you don't want to pay twice as much for your electricity than you currently do.

the per watt cost does not tell you everything, solar at about £1/watt is cheap but it only runs for about 10% of the time so its true cost is closer to £10/watt and that's before any grid integration and storage costs and problems. not to mention that a lot of people simply dont like huge areas of farmland to be turned over to black glass

If it did become cheaper you could potentially see solar PV go towards 10% of primary energy that is a lot but its a lot less than the 30-40% of primary energy nuclear could achieve

CLAPTON

Garethgrew wrote: »

Solar is now cheaper per GW than, nuclear, why we don't go over to clean renewable I don't know. Seriously why.?

how much does solar cost per GW at 7pm on Christmas eve?

cells

stator wrote: »

If the government practiced joined up thinking they would invest in hydrogen production built in to the new nuclear power stations. Require london busses to use hydrogen fuel cells and then expand it to taxis and eventually private cars.
It would massively reduce pollution and would make nuclear power stations more efficient as they would be producing hydrogen all day long and not just electricity.

hydrogen is a low quality fuel compared to electricity you wouldn't turn electricity to hydrogen to then use in buses or cars when you can use it directly

eg maybe instead bring back the trolleybus
https://en.wikipedia.org/wiki/Trolleybus

kinger101

cells wrote: »

hydrogen is a low quality fuel compared to electricity you wouldn't turn electricity to hydrogen to then use in buses or cars when you can use it directly

eg maybe instead bring back the trolleybus
https://en.wikipedia.org/wiki/Trolleybus

I think stator was perhaps referring to storing energy from excess output (e.g nuclear). Which means either hydrogen or batteries rather than running from the grid. Are there battery powered buses currently available? I thought it might be more problematic for larger vehicles.

cells

kinger101 wrote: »

I think stator was perhaps referring to storing energy from excess output (e.g nuclear). Which means either hydrogen or batteries rather than running from the grid.

You would rather just turn the nukes down if needed as the capital cost of a large hydrogen plant and distribution systems would make it uncompelling even at zero cost electricity

kinger101 wrote: »

Are there battery powered buses currently available? I thought it might be more problematic for larger vehicles.

batteries would work well for larger vehicles than for smaller ones as weight is less of a concern and they do more mileage per year to benefit from the supposed cheaper fuel

Battery trains should be feasible not only for the fuel saving over diesel but it costs a hell of a lot of money to electrify a track sometimes hundreds of millions or even billions. The weight of the batteries should be no issue on trains

Battery buses should also work. Their low speeds and start/stop nature should mean a massive jump in efficiency from the 6-7 mpg they achieve in London. Might get as good as 0.7 miles per kWh which would make a 200KWh battery bus very viable

chris_m

kinger101 wrote: »

Are there battery powered buses currently available? I thought it might be more problematic for larger vehicles.

https://www.stagecoachbus.com/The%20Electric%20Optare%20Solo.aspx

kinger101

CLAPTON wrote: »

how much does solar cost per GW at 7pm on Christmas eve?

http://www.teslamotors.com/en_GB/powerwall

stator

cells wrote: »

hydrogen is a low quality fuel compared to electricity you wouldn't turn electricity to hydrogen to then use in buses or cars when you can use it directly

eg maybe instead bring back the trolleybus
https://en.wikipedia.org/wiki/Trolleybus

Trolley busses are nice but probably not going to happen in London and definitely not in the rest of the UK. The point about encouraging hydrogen is that it could be used to power all vehicles eventually. You can keep it in a tank and top up at a petrol station, so as long as the infrastructure is there you have unlimited range, like petrol/diesel. So you start with busses because they produce a lot of pollution and are controlled by TFL, then you move onto taxis and then other private vehicles.

kinger101

chris_m wrote: »

https://www.stagecoachbus.com/The%20Electric%20Optare%20Solo.aspx

Seems good. I think the hydrogen buses are supposed to be about $1 million. So both are more expensive than a conventional bus. I guess its just a matter of how much scale and new technology could reduce production costs. The electric certainly would need any additional infrastructure.

I suspect batteries will win over hydrogen in the long run. There just seems to be more innovation. They will get lighter with new materials.