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We don't have peak demand from aircon in the UK (GB grid) either. Ours comes on (winter) evenings when, for example, meals are being cooked for kids home from school.

Do you have a link to your utility's site?

Yes, of course you shouldn't take my word on spec over your local guy's, but I'm stubbornly continuing to assert that your local load profile can't be completely flat and with rock-steady frequency even if not as tortured as elsewhere.

For reference here's my 'local' grid (GB) live balancing stats:

http://www.bmreports.com/bsp/b...

I am truly sympathetic to your wish to overcomplicating things and making them more complex and fragile: I just don't think this stuff will be 'over'-complexity for a huge chunk of the purchasers, it will be more like an essential and pay for itself in upfront balancing payments off the purchase cost in many cases.

Here are a few of my wacky ideas on the topic, one of which got me through the first round of a competition sponsored by National Grid and another of which has been discussed with an electricity supplier:

http://www.earth.org.uk/domest...

I will still try to turn some of these into niche (but simple) versions of consumer products. You only buy these ones if they meet a need for you and no one else is lumbered with the extra complexity...

Rgds

Damon

Goodness, that's rather offhand and completely wrong at lots of levels.

Clearly there a peaks at national and supra-national level. Have a look at some of these for just one example:

http://www.bmreports.com/bsp/b...

Flattening demand would reduce costs of infrastructure that otherwise has to cope with unrestrained peaks; we already do this so it is only a matter of degree and where exactly we do it. Further, allowing demand to follow non-dispatchable load will also help make better use of renewables as well as cope with failure of conventional plant more gracefully.

Also, different parts of the grid will have different problems, eg while the grid may be fine overall at a given moment one substation may be having a torrid time with its much smaller consumer sample, eg that may have a bunch of locals arriving off the same bus or train putting the water for a cuppa, or have a cable fault in one phase, or whatever.

Further, sensible secure schemes will devolve as much as possible of the detailed timing to the appliance so that they cannot all be commanded to 'come on' or 'go off' at once but apply a randomisation algorithm much as Ethernet does for example.

Just because you may have decided up front that there are no good solutions doesn't mean there aren't any. Some of the people that have them know a lot more about stats than you and I both, so can we at least accept that there are entire chunks of maths and computing that have interesting secure distributed randomised algorithms that deal with exactly these sorts of issues all the time?

Rgds

Damon

Take Scotland as an example. Using wind they meet your base load requirement. Yes, locally wind speed varies, but over the entire country there is always enough energy being produced to supply a certain amount of base load.

No there isn't (unless "a certain amount" is about 5% of installed wind capacity). This shows UK generation status. Wind has actually been quite stable over the past couple of days, but I've often seen it down near zero.

Furthermore wind speed is very predictable over the short term, and you can always keep some idling gas plants around to fill in those rare occasions when you need more energy.

Indeed you can, but what if you want, say, 50% of the electricity to be provided by wind on average? Baseload is about 50-60% of average (for the UK, which is what I'm familiar with). At a load factor of 30% that implies that at anything higher than 20% of electricity from wind (on average) means that sometimes there'll be more wind power generated than the grid can make use of. Generating electricity when nobody wants it isn't economic.

Hydro storage is pumped with whatever fuel is powering the grid at that moment, for which the ratio was only about 2:1 nuke:wind in the UK last night as it happens:

http://www.earth.org.uk/_gridCarbonIntensityGB.html

http://www.bmreports.com/bsp/bsp_home.htm

Rgds

Damon

recent data for UK

http://www.bmreports.com/bsp/bsp_home.htm

check out the "Generation By Fuel Type" tables ... if you imagine Germany gets something better you probably deserve the overcharge on your electricity bill.

>but I can say that in the UK, most of the planned wind farm projects will actually be more reliable than our crappy old aging gas/coal burners.

Well, you say planned, but we can check for the existing ones. When I looked, wind output had changed by a factor of 20 in less than a day - and of course that's uncontrollable, unlike a gas turbine.

>You can't shut it down easily to stop generating overnight, and unless somebody is buying power from it, it's losing money.

You don't need to unless your nuclear share above about 50% of average generation, as demand never drops below that. We're at less than 20% at the moment.

In the UK the ratio between peak and off-peak wholesale electricity can be about 10:1, and it turns out it's financially worth installing massive reversible turbines under mountain lakes to do it, so yes, with a similar cycle efficiency and a retail tariff strongly linked to wholesale prices (eg c/o "smart metering") it could be well-worth doing.

Rgds

Damon

PS. Looks like a more modest 2:1 or 3:1 over the last 48h or so: http://www.bmreports.com/bsp/SystemPrices.php?pT=SYSPRICE&dT=NRT