solar steam space heating

solar steam space heating

Given your unique knowledge and forum on steam heating I am wondering if you have heard of any applications to space heating of the many advances in solar concentrator technology, (mainly "solar trough" linear parabolic mirrors), that heat energy-carrying fluids developed mainly in the US that could become the new renaissance in steam space heating?
Specifically, in Spain, they are developing the only system that actually produces the steam directly in the concentrator.
Thanks

Question

How do you store steam all day for use at night? Usually when you have sunlight available, the structure also has passive solar gain. This is one reason I think hot water is the way to go when using solar.

-Andrew

Right...

There are two problems with using solar for either domestic hot water or for high temperature space heating. First, the collector to atmosphere temperature difference is high, and it is very difficult to insulate effectively; the efficiencies are startling low. Second, the problem of storage of a high temperature working fluid is similar: you have to insulate like mad, and you have to have a lot of it to carry you through (and you can't store steam, my friend, for any length of time at all, insulated or not).

This is not to say that solar isn't a good option for space heating, even here in New England. My father-in-law was one of the noted pioneers in the field, and has a number of 100 percent solar heated houses in Massachusetts and New Hampshire to his credit. Quite livable, too -- no fancy stuff. But he never did use solar for domestic hot water, except in one or two experiments. All the stuff that actually worked used air as the working fluid, generally at around 100 F, and water as the heat store, at a maximum temp of 120 F to 130 F.