OT: La Rance - peak power ?

KW are not volts.

The average *electricity* consumption is a lot less

Currently annual average is about 30GW, which is about - for a 60 million population, 500 watts.

Not sure what the Times is talking about - or through which orifice - but IIRC the total energy consumption equates to maybe 1500 watts per head. Onshore. How much coal is burnt in china to support our lifestyle is moot.

It wasn't the Times as such. It wss the phys Prof in his letter to the Times where he corrected some people's magical thinking. He said it's 4kW.

I use it as a shorthand term.

That's the current demand. What will be the demand when we are all driving EVs and have ditched all our gas and oil boilers in favour of electric heat pumps.

on 15/10/2021, Brian Gaff (Sofa) supposed :

Yes, that's the one - long straight across the barrage, with a tight turn on and off the causway.

Think we do have suitable estuaries, the Bristol channel would be more than suitable and also provide access to traffic between Devon and Wales.

Morecambe Bay is another one.

Now find 998 more...

Andy

There are a number of estuaries down the east coast that *could* be used, but no one in their right mind would (e.g. Dundee, Firth of Forth, Humber, The Wash, Thames). Unfortunately there are too many people around not in their right mind.

Well, it's based on what I use and a 4 person household.

On feasibility of tidal power, I don't know (obviously) but this team seem to have a pretty good idea (in 2008) a fair bit about all of this and it makes sense to me:

I think you're working on per person - per household would be roughly a quarter of that?

Well, I'll have to rely on you to do the maths, but the report I linked to cited one case study (Severn estuary ) capable of an annual average electricity output of 17TWh and a generating capacity of nearly 9GW (p.40).

Not trivial, but it's only part of my point. IMHO it's entirely wrong headed to project future needs as some sort of extension of what we do now, but more carbon neutral. We should be focussing on consuming far far less, with communal approaches.

I don't think individuals are capable of doing what needs to be done. The government is going to have to intervene and enforce change. The climate Rebellion people are pushing democratic means to all practical limits and it won't make any difference.

I'd hazard a guess he is doing 100 * 57MW. Nothing to do with household or people.

I think if we include heating and electric cars and variability we would need at least 100GW (maybe 200GW). i.e. 2,000 La Rance.

Hinkley 'C' is 3.2GW, 35 of them would do the trick.

What they, and you, don't apparently seem to appreciate is that there are times (four times each day, in fact), when any such barrage would produce ZERO power. There are two high and two low tides each day, and for perhaps an hour at each of these, the barrage would produce next to nothing. And yet if at the four peak times its producing lets say 8.64GW, then someone is using that. Meaning that you better have some means of producing 8.64GW in a cyclical manner with a 3-hour time shift.

Got any ideas for that?

You'll note that the item you linked to doesn't mention this issue. They do mention La Rance, without also mentioning how small its output is.

No, I'm working on the output of La Rance compared to current UK demand. It's very simple.

Exactly. And RJH seems unaware that the output from a barrage is not a nice constant 8.64GW, but varies with the tide.

Indeed - although worth noting that is the average output... sometimes it will be closer to the 240MW installed capacity, and sometimes it will be nothing. So no use for baseload generation at all.

There is some spare capacity between our peak and baseload overnight, so we can accommodate more for transport charging without extra capacity. However extra space heating load will drive up the daily peak. Probably not to as much as 100GW though.

or a bunch of SMRs

Only 2 - install plenty of them with complimentary tidal patterns. And have a secondary source for periods when tidal's insuffient and/or unavailable.

They do do comparisons - it does seem that the Severn proposal would be large by the standards of these things.

OK - I'll do the sums again at some point. I think I used 10 kW/day, not sure.

None of it? I see it took you 36 minutes to read it cover to cover and reply, so obviously due consideration ;-)

Just legislate and bring stuff into state control. Really not difficult.

Guardian? Make sense?

Dream on.