Inspiring stuff! You might find LightManufacturing’s Heliostat (the H1) interesting – see http://www.lightmanufacturingsystems.com/heliostats We’re using a tensioned membrane mirror for light weight and other advantages.

We’re using the heliostats for general purpose heating and lighting, but also in our Solar Rotomolding Systems. These make plastic objects like water tanks, entirely off grid. See http://www.lightmanufacturingsystems.com/videos

Our aim is to apply solar thermal / heliostat energy directly to manufacturing processes, with the aim of lowering costs and reducing greenhouse gass emissions.

Best,

Karl

Thanks a lot for sharing this article , it is very usefull.

I found this video: http://www.youtube.com/watch?v=ugt4sU1ketA

it is describing a heliostast solar generation project on a large scale ~ Mega Watts for a company called esolar.

they said the project cost was more than 110 million $ !!! why did the project costed all this ?

also what is the difference between the technology they are using and the technology used here by all of you guys to make a heliostast at home.

Thanks
Adany

@samhitha
If sunlight hits your neighbour’s wall then yes, in theory you could mount a heliostat to it to reflect the light into your house. In practice it may not be easy. Sorry, I don’t think there’s much I can do to help.

I only meant that it’s “comparatively easy” to get something to point directly at the sun. Depending on your electronics experience it can still be difficult.

Here’s an example of the easiest way I know to do it without a computer: http://www.youtube.com/watch?v=j_yqBdbuKpg. For each of your two axes of motion (azimuth and elevation control) you need two detectors aimed 90 degrees apart from each other (4 detectors in total). The example above just shows one axis. Each pair of detectors is wired in parallel but with reverse polarity to make what’s called a split detector. A split detector will output positive or negative current depending which of its two detectors is receiving the most light. You can use that positive or negative current to drive a motor that will turn your device until both detectors are receiving exactly the same amount of light, which will be when the line bisecting the two detectors points directly towards the sun. The example above uses PV cells for detectors. Those may output enough power to run a motor directly. If you want to use smaller detectors like photodiodes, you will need an amplifier circuit to drive the motor. See. Easy peasy!

Using a fresnel lens is a simple solution if your goal is to heat up a small object (ex a cooking pot or frying pan) to a high temperature. But if your goal is to move the energy somewhere else (ex to heat a home) I think you’ll find a fresnel lens is no simpler than other methods.

Thanks,

Regards

Brian

Err Um “ok, I think weve got a business here” lets form a company, chip in .. and go with what works so far..

ie; standardized 8mm toughened Glass mirrors, no frames, corners rounded and sanded safe for kids, bonded directly to a Plazma Screen type motorised tracking brackets, independently powered from its on board PhotoVoltaic cells, wirelessly N networked and GPS position aware, totally controlled via the Home PC software.
its so easy to visualize.

Sell em at Wal-mart, simply dig six or eight postholes in the yard, concrete in the posts, plonk the hi status Branded units on top, and aim 2 or three at each window, load up the software, and thats it, it works! The air conditioner moves the heat around inside to balance room temperature and when you come home from work around 6:30 pm, the house is cozey and warm enough to coasts into the next sunny day.

No more heating bills! And with PhotoVoltaic Solar Cell Trackers added to the system later on, no electricity bills either! Yeah!

Ok, whos in, and whos is top class a International Patent and Trademark expert??

Raymond

Also, the design pictured uses a single sheet of plywood as backing which results in quite a nice sail, but I have since switched to a metal frame with a 1/4″ gap between each mirror which I find reduces the wind load considerably compared to a continuous surface.

If the linkages are built well with no backlash, wind loads are tolerable. If there is any backlash in the system, then the wind load is amplified by inertia and will do more damage at lower wind speeds. My metal frame design has survived continuous operation for the past 2 years with gusts up to 50km/h. The only adverse effect has been loss of position reference (wind loads are enough to stall the motors, but not to damage them). The motors run for a fraction of a second every 10 seconds. If that happens to correspond with a high wind load, then the motors will stall and a small amount of expected motion will be lost. Over a long windy period that can result in the heliostat lagging behind it’s target position. In that case, it’s relatively simple to make a manual adjustment and push a calibrate button in the software to accept the current position as the correct one.

Still, don’t expect satellite dish robustness from this design. It is a relatively cheap design built by someone (me) who was willing and able to tinker with it on an ongoing basis to keep it operational. Building for a consumer market is a different thing altogether.