Tuesday 6 October 2009

Municipal Solar?

Ok, now let me run this scheme up the commentary pole and see who cheers (or jeers...)!

I've argued over at LP for a while that councils should look at developing municipal solar energy. That is, use the greater scale of council buildings, vacant property (and rates) to generate larger-scale solar power and feed it in to the grid at local area level. This would offer clear economies of scale in greenhouse abatement - that households can't hope to achieve - and produce larger volumes of power per dollar. Equally (by reducing net consumption of non-renewable energy across the municipal area) it would financially benefit all (both ratepayer-owners and tenants) by reducing household power bills in the mid to long-term. Households would receive the generated power as 'pre-paid' solar, at no further cost.

Households with private solar would get a double benefit, the rest would benefit by the effective socialisation of solar at the council area level. Perhaps they also could cut deals with state governments for the use of vacant Crown land.

Essentially, its a variant on the old school municipal socialism idea: in Britain in the late 19th and early 20th century councils were in the front line of creating public ownership of tramways, gas, waterworks and other utilities, using their greater collective buying power.

11 comments:

robert merkel said...

On the bright side, it makes a heck of a lot more sense than home rooftop solar, which is a boondoggle.

That said, there's still severe doubts as to whether any solar PV tech makes sense as a large-scale energy source. How long should we keep trying before we collectively decide we're just throwing good money after bad and instead try solar thermal, geothermal, wind, wave, etc. etc.?

Fyodor said...

Economies of scale aren't the problem, and wouldn't compensate for the inherent inefficiency of photo-voltaic energy relative to existing alternatives. Which is kinda Robert's point.

The council would be pissing money up against a wall. Not that they don't do that already, o'course.

Liam said...

If the councils are going to get into the business of researching, manufacturing, distributing and installing the PVAs, then certainly, yes, it's a variant on old-school municipal socialism. Even if they were run at lossses, public-owned tramways and utilities always came with significant user fees attached.
To lower myself to the traditional pro-market argument (and I feel dirty, belive me): if it's so useful, and given the level of Commonwealth subsidy, why isn't anyone doing it for money already?
As boxhead says, it'd just be pissing council money up against a very expensive wall---every council can probably name half a dozen childcare and long day care centres, or disability respite care services, and so on, that could keep on staff with the same money.

Lefty E said...

well, 3 jeers for me!

A few points:

I think Council's owning them would be enough for the parallel to be sustained, Liamista - though that's just an aside.

Im not expert in these technical matters by any means Rob - but I did hear something about Spanish advances in energy storage from solar. Im not suggesting people act NOW - happy to wait for the critical advances. I just think it could be a good model - and for that matter - a model that could apply to ANY renewable source.

Another minor quibble, Liam: Im pretty sure part of the prob here is that govt policy setting actually DONT subsidise larger scale solar. Thats part of the reasons you see some people removing panels from their rooves.

And Fy - again, no idea of actual numbers myself- but I DO gather part of whats so crap about rooftop solar is the amount of hoohaa, cost, and embedded energy per watt you get out of rooftop. At some point in "size" that has to get better, as in more efficient.

Liam said...

I'm still curious about how you'd expect an LGA to prioritise a budget in the context of overlapping State and Federal responsibilities, Izquierdista.
Solar arrays with rebates for power-hungry business-owners, or recurrent funding with CPI increases to
the childcare centres and the library?
[mutters something about comparative advantage, has to go and get Ricardo off the shelf]

robert merkel said...

Lefty, the Spanish system is for solar thermal.

In essence, you use mirrors to focus direct sunlight on something. It gets hot. You use the heat to boil some water and run it through a steam turbine.

What Torresol does is use a tank of molten salt as a heat reservoir between the sunlight and the water. You use the sun to heat the salt. It stays hot until, at your leisure, you run water near it, turn the water into steam and run it through a steam turbine.

Solar cells obviously work completely differently, directly converting solar radiation into electricity, which is great - except that they cost a fortune and electricity is a lot harder (read: more expensive) to store than heat.

The thing with just about any thermal power plant, however, is that the bigger you make it, the cheaper it gets per unit of energy delivered. There are two reasons for this. One is that it doesn't cost twice as much to build a steam turbine twice as big. The second is that big steam turbines are inherently more efficient than small ones using similar technology.

So the Spanish solar tech (and they're by no means the only ones doing this, by the way) works best if you make it at similar sizes to current conventional power plants, which is a little bit beyond the scope of just about every local council in Australia (city of Brisbane excepted, perhaps!).

Solar PV panels are subject to rather different cost scaling laws.

Solar panels are produced as modules, so (aside from perhaps cutting out a retailer) it costs about the same per unit if you buy 1000 of them as buying one.

However, the electronics to convert the power to 240 volts and feed it back into the grid does become a lot cheaper when you buy industrial-size. So does installing the panels. The numbers I've seen suggest this cuts the costs by maybe a factor of 2 compared to home-scale PV units.

Even so, a factor of 2 cost reduction doesn't get you anywhere cost-competitive with a whole host of other renewable options, including some of the ones I mentioned above.

Lefty E said...

The short answer to your Q Liam is that its not a zero-sum budget game - the idea of municipal power generation would be to reduce power bills for members (residents). Whatever power it generated is paid for - collectively - by ratepayers and them comes free to those same residents - reducing their non-renewable power bills.

That allows you to charge it as a separate levy on rates (larger at set up, smaller at maintenance phase) without those ratepayers being worse off.

In other words - it doesn't mean something else has to miss out in the budget pie.


I dont doubt Rob when he says there's current problems in doing this is PV - but that may change with technology, and its also just a model that could be employed.

Maybe I am overly influence by Brisbane (since Im from there) but the Bushland acquisition levy works in this way - it collectivises contributions and gives purchasing power - it doesnt come from rates per se, but is simply paid that way, at the same time.

Liam said...

Sure Lefty but in that case you have to either borrow or spend from a surplus to buy into the scheme in the first place.
Now I'm not saying that's not a valuable thing for Governments to be doing---I am after all pledged by an unholy blood oath to serve the labourist ghosts of Bill McKell and Joe Cahill---I just question that deficit spending on power generation is a valuable thing for arse-out-of-pants shires and councils to be doing with their already-probably-in-hock assets.
Alternatively, if it's so economically safe a bet that nothing has to come out of the budget pie, it sounds to me like private capital ought to take a bit of risk.

Lefty E said...

All profits to members c'rade! I actually reckon private capital are relatievly inefficient at such schemes: eg they tend to want to take a portion as profit to shareholders, above the admin costs any scheme would have to fund.

Its also presumed in the model that they are building them on, in, or above existing property.

And not nec. re the deficit spending either - the BCC, eg, didn't actually buy any bushland from the levy scheme until they had enough dough in it, in its third year.

RobV said...

I agree with the point by Lefty E that local municipal councils are at a good scale to install and run renewable energy installations, especially for solar power in Australia. I think that thermal solar power stations would be more cost effective than PV and could deliver larger amounts of energy for the money invested in building the installations. One good place where solar thermal (ideally with Linear Fresnel Collector arrays) could be built is near rubbish tip sites so that the biogas that is collected at the site could be stored and burnt as fuel in the power station heat engines at night or when it is overcast. You could also have some form of thermal storage at the site or store other kinds of fuel. The heat engines could be chosen so that they could be used with a variety of energy sources, for example like Stirling engines or perhaps Organic Rankine turbines.

I would also prefer to see power generation being seen to be a responsibility of governments at the various levels or collective organisations rather than throwing that responsibility into the lap of private individuals. It would be cheaper to build a network of small to medium scale distributed power stations located within residential areas rather than trying to aggregate a large number of privately owned micro installations or relying on a few mega-sized power stations built a large distance from urban centres. Wind farms can only be built in a limited number of places. One problem with PV panels is that people tend to move house every so often.

Distributed solar power stations built and maintained at the local council level could be an optimal way to generate electricity. It would also be at a good scale to store energy with the grid in sodium-sulfur batteries and the like. It also has the advantage that unlike large commercial ventures for solar energy, they would be at a lesser risk of going broke and having the whole project cancelled. You could still have commercial companies that specialise in designing and building solar power stations for councils.

[The comments above were first posted at LP]

Linear Fresnel Collector solar thermal arrays wouldn't be able to generate temperatures as high as you have in coal power stations. Solar power towers might get close but they are more complicated and might be considered unsightly like wind turbines. Another problem with solar thermal is that there would be lots of times when you might be at 'lukewarm' temperatures for the heat engine. What would you do when the temperatures and pressures are just quite not high enough to drive a high efficiency turbine? It might be better to aim for a lower efficiency heat engine that can run most of the time on lower temperatures than you would find in coal power stations.

Lefty E said...

Thanks for the (partial) repost, RobV! I'm really just sitting here examining the issues from a political perspective - Im not much on the tech side. But using the rubbish tips fits well with the local govt approach.

And on that - thanks Rob Merkel for the last post which explained the Torresol deal. Interesting. Plain old Salt huh? I wasnt expecting that.

As for reflecively handing it all over to the private sector - meh. What have they done for us & greenhouse abatement lately? Id rather have a greater level of public control in this things - but Ive moved on ideologically too: id rather see it owned at the local level, where there's greater proximity, access, accountability and control.