NMT Reduced Cost Heliostat

The New Mexico Tech Reduced Cost Heliostat team seeks to reduced the cost of heliostats, ensuring that solar energy becomes a viable, competitive source of energy in America and worldwide. This video shows a demonstration of the team's heliostat prototype, performed in Fall of 2007

Category:

Science & Technology

Tags:

• heliostat
• solar
• energy
• power
• new
• mexico
• tech
• sun
• alternative
• fossil
• fuels
• green
• technology

[rstevewarmorycom]

Why doesn't anyone know how to build an equatorial mount

anymore, it reduces the problem to a single rotational motion.

whether a simple sun-tracker or a true heliostat, it simplifies

design, but I keep seeing these two axis monstrosities that

aren't even properly counterweighted.

[KindSirJubbuk]

@rstevewarmorycom Using a heliostat with a single axis of rotation is absurd for realistic power tower applications (our goal) - think seasonal sun elevation changes and the freedom to reflect sun wherever you want on the tower.

People know how to make equatorial mounts still, since.... heliostat's like that already exist. The goal of the project while I was on it was to test a NEW drive system, which required that we use a two-axis system. I was not involved in the design of the structure.

[danie1murphy]

Why so large? And why are there human legs in the first 10 seconds of this video. Isn't

smaller the way to go with heliostats?

Dan

[KindSirJubbuk]

@danie1murphy if you were to read some literature, you'd find that, in general, larger is better. Typically, cost is measured by the available reflective surface area, so a small mirror ends up being inferior. However, companies like eSolar are exceptions.

[danie1murphy]

@KindSirJubbuk Thanks for the reply. Yes, large is good, but the cube problem comes into play. As each dimension of the object is doubled it's weight is cubed which might make it cumbersome for the home owner on a small scale. Also, what are the neighbors going to think?

[KindSirJubbuk]

@danie1murphy I see what you mean. There is a more complex relationship than just weight however - as the structure changes in size, it's design changes, as the design changes it often requires different hardware which can be expensive. Studies suggest that larger is still better, at least for large scale heliostat fields - prod.sandia.gov/techlib/access­-control.cgi/2007/073293.pdf .

It's sure to cause trouble with the neighbors, unless you invite them over to work on that tan.

[KindSirJubbuk]

@danie1murphy link doesn't work of course - google "Heliostat Cost Reduction Study", it's a pretty good paper.

[danie1murphy]

@rstevewarmorycom Please see my video, not a very good one, on the straight equitorial mount problem. You will have to pause it on occasion. Yes, for special applications. equitorial-polar mounts work wonderfully.

[c33r0k33]

@Davetech23 Nice thing about heliostats is there are a range of applications, from producing household lighting to providing heating of interior thermal mass to providing solar energy generation in terms of heat, amplifying pv output, steam generation, amping solar hot water producing, solar hot air production. Heliostats can range from simple manual mirrors to (& what seems more practical to me) servo/computer models like the one on the video. Many municipalities are protecting solar access.

[connolly113]

looks impressive