Solar catenary reflector vid 2: asymmetrical design

[ke4uyp]

The major mechanical problem with this design is to obtain maximum efficiency the mirror must be oriented to the same angle above the horizon equal to your latitude.

Another words the mirror must point at the celestial Equator. Unfortunately this will distort the natural gravity produced curve.

[bjaygeek]

a search for catenary reflector came up with a program called R-Bench. Have you used it? It allows for asymmetrical catenary curves.

[thoxbui]

Yes, it is written by B. Schaffhausen, I have an earlier version of it on my website. Very nice gentleman who took the time to write the cool calculator and distribute it for free!

[macrumpton]

This is an interesting concept but unless I am misunderstanding you, most of the reflector (in this asymmetric configuration) is not concentrating. The interesting part of your idea is that you could make a solar collector that is very portable. Mylar with a few poles taped to it would work easily, and it could be rolled up for transport.

By adding poles of different weights on different parts of the curve you could still have the angled reflector, but the weights would correct the asymmetry.

[gaiatechnician]

I have a new video about the "kyoto trough" where I add little wings to a trough to get more concentration. I have only done it in software so far and it works. Perhaps it works with your catenary too?

Brian

[seancap08]

Beautiful. This has endless applications and is easily combined with the parabolic and trough methods.

Thank you. Heat your house or run pressure differentials for nuthin.

[olkids3a]

very smart,i hope and pray for your success.please share your creation with some less fortunate countries.are you asian?we are from the philippines.good luck.

[WellSpamSucks]

Very interesting!!!

[danboarder]

Great ideas, thanks for sharing!

[sockosockosocko]

hi tho

the laser demo is neat but as you move the laser up and down, the angle of light hitting the paper(or pv cell) changes drastically, right? how is this different from laying a pv panel on my roof all day? the sun will hit it all day but at different and less beneficial angles. angles of attack is not good, but intensity is greater?

THANKS for your videos!

[thoxbui]

Hi. This whole approach focuses on reducing cost, not foot-print. If the application is space or footprint limited, one needs to find the best efficiency possible. When available space is NOT an issue, by building an oversize collector cheaply, one can put out more power for a given investment in cash, knowing that not all of the available sun light is captured. Thanks for your thoughtful comment.

[pupplesan]

A compound parabolic reflector is the most efficient non-tracking two-dimensional shape. Your design of course has the virtue of 'self-formation', but the laser demonstration isn't helpful because you are aiming the incident beam at a single point on the mirror surface. With sunlight falling over the entire surface, the focus will blur far more destructively as the sun recedes from the focal axis.

[thoxbui]

Thanks for your comment. This is just a demonstration video to generalize on the concept. If you're really interested in understanding the behavior of this reflector, you are welcomed to visit the website for more information, and/or contact me for the actual mathematical calculations.

[Dave51262]

Really interesting ideas. I look forward to more of your videos. Thanks!

[bruceleasure]

I noticed that you brushed off the impact of wind on the hanging mirror. While I agree that a reforming mirror solves part of the problem, there is the other problem of not working well while the wind is blowing. It would be easy enough to put the mirror in some type of box with only the aperture needed for the sun removed. This would reduce the impact of wind on your ability to gather power.

[prefermetal]

Love it. Was wondering about the actual sun going from E to W as well as up down but you explained and showed this. How long/wide are the Mylars strips? They seem to be longer than needed. Is the catenary very close to the parabolic curve. Main criticism is that you can't make out the orientation of the mylar strips. Are they level or sloping. The camera needs to be moved abd the lightning improved. An excellent system. and cheap. The KISS concept that you just can' beat.

Best regards.

Dennis.

[BeeRich33]

Does your current model shown not demonstrate a higher focal point? You might want to draw up some kind of jig with a distant incandescent light, with a way of raising the height of that paper, to see if there is any kind of relationship of your scale.

[thoxbui]

Good observation. The model (at my website) shows that as the angle drops, the concentration of light is actually a little bit higher than the top level. It also moves back about 20-25% of the length of the mirror for the range I estimated. It actually doens't have a focal "point" per se, more like a region of high density of light. This is good for a PV target, because it reduces the risk of destroying the cell. But it isn't as good for solar thermal applications.

[Odziz]

Amazing! can't wait for the next video

[kheston]

Be sure and post videos of more working models.  I'd be particularly interested in any efficiency gains you're able to demonstrate. Failing that, efficiency compared to that of a tracking parabolic reflector would be interesting, too. Thanks for posting. Keep up the good work!

[thoxbui]

Thank you. I've made some rudimentary models and got some rough measurements. I will try to make a video and update my website as soon as I can find some free time.txb

[z500zag]

Thanks for putting this together. Great idea.

[mercedezzz]

Very cool!