PV Gap

Christy Said:

How Efficient are Photovoltaic Silicon Solar Arrays?

We Answered:

This video doesn't really show arrays. They seem to be a networking system that might be powering itself by solar, not generating extra electricity for the grid. Maybe the concept drawings at the beginning show that. Either way, it depends on what efficiencies you are referring to. Efficiencies have different understandings to different people.

Angel Said:

Is photovoltaic array another name for solar panels?

We Answered:

A photovoltaic array is 1+ solar photovoltaic panel, the kind that produces electricity. All photovoltaic panels can be put together to be part of a photolvoltaic array and all photovoltaic panels are solar panels.


However, not all solar panels are photovoltaics. There are also ones that heat water, these are different from photovoltaics.

Here's solar heating panels:
http://img.diytrade.com/cdimg/727694/588…

Here's solar photovoltaics:
http://www.segen.co.uk/images/PV8.jpg

They not only look different, they act completely differently!

Rodney Said:

From an environmental standpoint, is it better to convert to Natural Gas from #2 Oil or Install Solar Panels?

We Answered:

Solar

Jenny Said:

Could we build a high speed electro magnetic levitation bullet train in outer space?

We Answered:

Nope, not really.

Because the radiation bursts from the Sun will knock the magnets out of whack or actually permanently damage them every few months.

I don't think anyone wants to replace 1 million dollar magnets every month in space.

Sean Said:

Is there better solar technology than Emcore Corp has?

We Answered:

Is there a worse technology?

This 2 axis solar tracker is expensive and with so many moving parts, would be subject to breaking down. Cleaning maintenance is harder than conventional PV arrays.

If you want 40W of power - a square metre PV panel will do a better job at a faction of the cost.

You can see from their web site, they're looking for some starry eyed investors to part with their money. I doubt that technology will ever be commercially compeditive with conventional PV panels.

(edit) Doesn't take much to impress you Boom - you go ahead and buy some stock in that company so the directors can sell theirs.

The equipment isn't the size of a dime, just one small part of it is. That's like saying I have an engine with spark plugs so small they can fit in my hand, or I have a computer with a CPU the size of a wrist watch.

(edit) The customer doesn't need less land, they will likely need more land. They also need lenses and tracking motors control systems. If you guys are so impressed - buy some stock in the company.

Michelle Said:

Are there better point angles for alignment of photovoltaic solar panels given a seasonal usage?

We Answered:

If you Google "solar modeling software" or similar terms, you will find various programs people have created for modeling the sun falling on a location, given a particular latitude and longitude. An example is at

http://www.f1.fhtw-berlin.de/studiengang…

but I'm not endorsing that program in any way.

There is also insolation data for the USA gathered by the National Renewable Energy Labs at

http://rredc.nrel.gov/solar/old_data/nsr…

The above is VERY good, as it is real data gathered over decades, and as such, takes into account the effects of clouds, prevailing temperatures, winds, etc. You could go month by month with that data, and model a particular tilt.

In general, if you want to crudely optimize for summer, go with latitude MINUS 15 degrees in the northern hemisphere. You will also want to make sure the panels are mounted with good airflow around them (that is, not flush against a hot roof surface), as you can lose 10, maybe even 20% of the production when the panels get really hot.

Consider also whether you might be able to grid-tie and net meter your solar (check with the power company) - in which case, you would build up a financial credit during the winter. If the array is in the thousands of watts, that would make sense.

If you are just thinking about small, point light sources, with (say) rechargable NiCd batteries, then I'd say it sounds like fun, but would be hesitant about either the cost or the performance of the lights. Hope it works out, just the same!

Elsie Said:

I would like to design and build my home. What kind of income would this entail?

We Answered:

There are magazines and other sources that provide approximate cost per square foot for various types of houses (although maybe not as modern as what you describe).

Your salary should be enough (depending on location) and certainly the more you save up before starting, the better. Banks will make loans after some to most of the house is built so that they have an interest in something besides a dream - - so you might have a lean year in the checkbook while your house is being built. Good luck.