reports on a development at MIT of a way to capture sunlight and create steam at high levels of efficiency.
A new material structure developed at MIT generates steam by soaking up
the sun. The structure — a layer of graphite flakes and an underlying
carbon foam — is a porous, insulating material structure that floats on
water. When sunlight hits the structure’s surface, it creates a hotspot
in the graphite, drawing water up through the material’s pores, where it
evaporates as steam. The brighter the light, the more steam is
The new material is able to convert 85 percent of incoming solar energy into steam — a significant improvement over recent approaches to solar-powered steam generation. What’s more, the setup loses very little heat in the process, and can produce steam at relatively low solar intensity.
Steam, of course, is useful for sterilization, desalinization, and cleaning. Most current systems for solar steam generation are huge, with lots of mirrors
or lenses collecting the energy concentrating the solar input up to 1000 times. This system requires much less of that.
By contrast, the MIT approach generates steam at a solar intensity about
10 times that of a sunny day — the lowest optical concentration
reported thus far. The implication, the researchers say, is that
steam-generating applications can function with lower sunlight
concentration and less-expensive tracking systems.
This is preliminary and hasn't been scaled up to full production, but it's something to keep an eye out for. The obvious advantages for sterilizing water in places with too much wildlife in their water supply are just one use. Don't neglect sterilizing surgical instruments for field or bush hospitals.
Steam is good stuff (when under control). A thing like this could be useful, someday, for getting off the grid.ReplyDelete
See what large scale steam can do.
Don't see why it can't be applied in smaller scale if it can be generated cheaply.
It's one thing to produce low volume, low pressure steam. It's another to produce it in enough volume, pressure, and temperature to do something useful like drive a turbine.ReplyDelete
But using it for desalination/purification is excellent!