(Apologies for the typo: my reply to Shadow should of course have said "unsupported conjecture", as there was no reason why a solar thermal plant woud never replace the coal plant)

Aiden probably our greatest problem in the world is the fact that Government have decided to dud all the savers. Interest rates are as low as they have ever been and there is abundant money so saying low cost finance is needed is a nonsense. You mean no cost finance, free money, well good luck with that.
Our greatest problem is the dishonesty involved in these green schemes and finance. Next time the world cannot trust itself to pay it's debts we will really be up against it. Lending Billions for school halls will not save us again. In fact it did not save us last time we are still deeply in trouble. Rudd the idiot is now posturing as some overpaid multi millionaire UN man, not just disgusting but pathetic!

Aidan,

The only way a solar thermal plant could run without a huge feed in tariff would be if the government paid for the whole project up front and wrote off the capital, as the present plants are only viable with a feed in price nearly 10x the coal generation cost.

Secondly, the solar thermal plants provide some power for the evening peak, but can't supply 24/7 even without overcast weather. If there is overcast weather, they produce next to nothing which leads to the massive feed in cost.

So in their present state, they don't fully replace a reliable coal based system, even ignoring their monstrous cost.

Some people suggest that to get 100% reliability and that is what we
need, I know I know, to all intents and purpose that is what we have
now, the cost becomes astronomical even suggesting infinity dollars.

We cannot afford it. Someone needs to work out how long it will take us
to build enough nuclear power stations at the rate we can get the
money together. Once that is known we can ration out the coal we have
to keep the show on the road during the build.

It has now become obvious that solar and wind cannot do the job.
All round the world the solar wind systems are not coping.
However the politicians are not even aware that there is any doubt.
They are charging on with plans for more solar and wind without even
asking if it will work.
If they continue on and you live or work above the third floor then
move or get another job.

Shadow,
"The only way a solar thermal plant could run without a huge feed in tariff would be if the government paid for the whole project up front and wrote off the capital, as the present plants are only viable with a feed in price nearly 10x the coal generation cost."
Here you go again with your unsupported conjecture! What present plants are you referring to? Who calculated that cost? What data did they use and what assumptions did they make?

Even if the present plants required such a high feedin tariff to be viable, it wouldn't necessarily follow that the government paying and writing off the capital cost upfront would be the only alternative way to make it viable.

"Secondly, the solar thermal plants provide some power for the evening peak, but can't supply 24/7 even without overcast weather."
That depends how they're designed. If they have a high heating capacity, high storage capacity and relatively low output capacity they can. But aiming to supply 24/7 would be a big mistake IMO – you don't need to replicate the undesirable features of coal fired power stations. Far better to concentrate on the times when the demand (and hence the wholesale electricity price) is highest, and buy cheap electricity from elsewhere at times of low demand.

"If there is overcast weather, they produce next to nothing which leads to the massive feed in cost."
It's pretty rare to have overcast weather when it isn't windy. But such occasions do occur (e.g. today) so contingencies do need to be made. The simplest (and cheapest) solution is to add a backup boiler running on gas. But it's not the only option. A more complicated, more expensive, but perhaps ultimately better value alternative is to colocate some ceramic fuel cells there – these generate electricity more efficiently than gas turbines, but they require a high temperature to operate.

I think those windturbines are the biggest blight on the country
side. They are just so ugly.

A visual pollutant. Horrible.