PV Gap

Danielle Said:

what is the efficiency of the best solar cells today? Also, is biodiesel feasible considering limited land ?

We Answered:

I have installed my own solar system and am in the process of starting a solar company. I have included links to all the companies mentioned below. The very first link is to the Energy Blog's Solar PV section. There are dozens of articles about companies that have plans to make or are making solar PV products. The field is very fast growing and there must be well over 100 companies making solar PV products.

The highest efficiency solar cells currently available is about 37% but only under concentrated sunlight about 300X stronger that normal sunlight. This type if cell is intended to be used with a lens or mirror to concentrate the sunlight. They are quite expensive but only a very small number is required compared to normal cells. These cells are made by Spectrolab. There are more than a dozen companies working on making products that use these cells. Most of them will be sold to commercial or utility companies to generate solar power on a large scale.

The highest efficiency normal silicon solar cells is just about 21%. These cells use the highest quality electronic grade silicon wafers and use back side contacts so that the entire front surface collects power. They are made by SunPower.

Normal efficiency crystalline silicon solar cells are about 15% efficient. If you were to buy normal solar panels from a company like Sharp Solar, BP Solar, General Electric etc. That is most likely about the efficiency of the panels. You can buy solar panels made by these companies at the Alternative Energy Store on-line - links below.

There are a number of companies selling and working on several different types of thin-film solar panels. These panels are less expensive ranging from about 8% to 12% efficient but they are also fairly in expensive. Examples include Unisolar, PowerFilm, Kaneka