Heliostats and heat storage

[Myrtonos]

Heliostats are gaining popularity as an economical method of daytime indoor lighting in sunny places. But this trend seems quite recent in relation the technology behind heliostats, these having been invented centuries ago.

Some solar power stations have heat storage, usually with molten salt, in addition to heliostats, and even these seem quite recent in relation to the technology involved, what if molten salt heat generation in conjuction with Heliostats had appeared in the 19th century?

 

[carlton_bach]

I'm not sure it would have been economical. Mirrors and large glass panes are difficult to make without modern industrial technology. As late as the 1950s, big windows were status symbols.

 

[Myrtonos]

I but windows have been a feature of buildings in civilisation since long before the industrial revolution. I didn't know that big windows used to be status symbols.

But heilostats don't necessarily require big mirrors, they could surely use more smaller ones.

And how modern is 'modern' in this case? Post-1900?

And the cost of making mirrors and glass panes of any size is not ongoing, so the low running costs of Helistats would surely have eventually paid off.

 

[NCW8]

I but windows have been a feature of buildings in civilisation since long before the industrial revolution. I didn't know that big windows used to be status symbols.

But heilostats don't necessarily require big mirrors, they could surely use more smaller ones.

And how modern is 'modern' in this case? Post-1900?

And the cost of making mirrors and glass panes of any size is not ongoing, so the low running costs of Helistats would surely have eventually paid off.

For large sheets of glass, you need the Float Glass Process, which was developed in the 1950s.

In medieval times, flat glass was made by being cut from a disc of crown glass, which was made by spinning a bulb of molten glass, like this:

There's obviously a limit to the size of the glass sheets that could be made by this method, which is why your classic Olde Worlde houses have windows made from lots of small pieces joined together in a frame. You also end up with the thicker bit in the centre, that also features in such windows, because this was the cheapest part of the glass - unlike modern recreations.


Cheers,
Nigel.

 

[Julius Vogel]

Well glass does break, a lot and I would imagine that would have been a bigger problem pre 20th century and the widespread advances on materials technology that has made glass stronger/safer.

I believe there have been a lot of industrial advances in the late 19th-mid 20th century that made glass easier to produce in large sized sheets. Whilst it may have been possible to produce such earlier, I would imagine it would have been much slower and more expensive.

 

[Myrtonos]

So some of these advances were in the late 19th century, that was when steam engines were still used extensively.

Thing is that most others were in the mid 20th century, but even then, Heliostats didn't catch on.