Thursday, January 7, 2010

Global Solar Energy Adds Two New Portable Solar Chargers

Portable solar chargers are an up and coming items for those seeking eco-friendly means of portable power on the go. Here at the Consumer Electronics Show this week Global Solar Energy, a manufacturer of Copper Indium Gallium diSelenide (CIGS) thin film solar products, is showcasing a few new models from its SUNLINQ line. These are known as the USB Mini and USB Plus.

The SUNLINQ USB Mini and SUNLINQ USB Plus portable solar chargers are designed to harness the sun’s energy to charge mobile devices like phones, PDAs, iPods, and electronic readers. These chargers deliver energy to these devices directly through a USB port, charging their internal batteries directly rather than storing energy in an internal battery of its own for later charging.

Features of these portable solar chargers include flexible solar energy cells so that the chargers can be laid out or attached to better optimize sunlight, a weather resistant, nylon rip-stop backing, 5-volt standardized USB power and charging under even cloudy or overcast skies.

What is the chemical process that takes place in a solar panel?

On a chemical level, how does a solar panel work? What are the chemicals inside it that react with one another, and how are the chemicals arranged and assembled with the other materials?

Specifically, I’m trying to determine if I could build a solar cell at home, even if it is very inefficient. Any information is appreciated.

Nothing chemical at all – solid state physics at the quantum level – photon of light knock electrons off silicon which are freed to form an electrical circuit that we can use as power.
Because nearly pure silicon is required, there is no way you can build one of these at home.
Heating solar panels are not chemical either – just physical.

Solar Boiler

Efficiency of Solar Cells

Since the introduction of the modern silicon solar cell, the efficiency of solar cells has improved significantly. The first silicon solar cell was created by Bell Labs and shown to the public for the first time on April 25, 1954. This solar cell was able to convert about 6% of the solar energy it collected to electricity.

The silicon solar cell followed the selenium solar cell, which was significantly less efficient. Selenium solar cells only converted about 0.5% of the sun’s energy.

Most research on solar cells since that time has focused mainly on improving efficiency and decreasing manufacturing costs. So far, researchers have succeeded in creating cells with up to 40% efficiency, using exotic materials. However, using these materials significantly increases the production cost; these high-efficiency cells can cost over 100 times as much as ordinary 8% efficient cells to produce. Decreasing production cost may be even more important than improving efficiency in relation to the goal of encouraging more users to adopt solar power.

The total amount of power provided by the sun under ideal conditions is around 1,000 watts per square meter. These are the conditions that are assumed when a specific solar cell’s output specifications are cited. Of course, there are a number of factors that can impact the intensity of sunlight, such as weather, elevation, pollution, and dust. Some events, such as volcanic eruptions, can even reduce sunlight on a worldwide basis for periods of a year or longer. Elevation has an impact on solar cell efficiency in that higher elevation actually brings greater efficiency. This is due to the fact that, as elevation gets higher, the air gets thinner, and the effects of dust and pollution are decreased.

At approximately 14-19% efficiency, multicrystalline solar cells are the most efficient cells currently on the market. However, this kind of cell is not expected to improve much beyond that benchmark. Amorphous silicon cells, on the other hand, although currently about 8% efficient, are widely thought to be the next big thing in solar cell technology.

How to Install a Solar Air Heater

I am not as handy or have as much time on my hands as some.

Therefore I purchased a manufactured solar air heater / collector.

It is a good unit and is providing up to 80 degrees F temperature rise at its peak.

What I did do was to take meticulous notes and pictures of the installation process of the unit against the south wall of our walkout basement.

If you would like to review how we installed it, as well as of the unit itself, you can access our blog entries with lots of pictures here:

Solar Air Heating Installation Series

I will also say that, however, that before investing in any energy conservation product one should undertake the no cost and low cost energy conservation tasks first. This approach will also provide the funds over the short & medium term to pay for the higher cost energy conservation investments.

I hope this helps,

Solar PV Firm Bets on Bioplastic

Shrink Nanotechnologies is one of several companies that is using bioplastics to find a new way of making devices that will minimize the use of increasingly-scarce rare metals.

The company’s OptiSol Solar Concentrator is billed as a nanotechnology-based plastic solar concentrator and solar photovoltaic cells film. Traditional silicon solar cells absorb only a small fraction of the total incident solar radiation potential, with a majority of the light either reflected or converted to thermal energy.

Based on electromagnetic non-optical principles and using a proprietary technology, the OptiSol enhances the capabilities and efficiency of existing solar cell designs by focusing and tuning the incident solar radiation from the sun for optimal silicon absorption, with less of the total spectrum lost as heat or reflection. The goal is to deliver immediate and significant improvements in efficiency and power output.

The product can also be made into clear view solar cells that can be used on windows and for exterior panel siding.

CleanTechies caught up with Shrink Nanotechnologies CEO Mark Baum for three questions.

CleanTechies: Do you have any working installations? Where and when were they deployed?

Mark Baum: We are currently building a final prototype functional OptiSol solar window with our working groups at UC Irvine and UC Merced. To our knowledge, this device — including the first two iterations — are the first functional quantum dot solar concentrators that do not rely on mirrors, lenses or tracking systems. They absorb ambient light at one wavelength and convert it into another (800-900 nm). We use very small amounts of silicon to absorb at the 8-900 nm wavelength, and the efficiency of the silicon is improved as a result of the window design system that the silicon cell is a part of. Our current designs absorb approximately 16% of the light shining onto it and are at an overall efficiency of 5.7%.

To our knowledge, the most efficient concentrator device ever made is at 7%. Relative to the present efficiency numbers we have achieved, the additional differences are in cost. The fact that our window designs are upgradable, allowing the consumer to benefit from better technologies over time, and environmental friendliness as we do not use harmful toxic elements to create these results.