We have been reporting in recent weeks on a flurry of theoretical advances in solar energy technology. Most of these have had to do with nanotechnology, and promised improvements to existing designs in a matter of years, if not decades.
Although this research is clearly important as all efforts should be made to improve the technology as much as possible in whatever ways necessary, it is also important that improvements are made which can be applied to present production techniques. That way efficiency can be improved potentially in a matter of months rather than years.
This is exactly what has been carried out by IMEC, and presented at a recent conference in Spain, the European Photovoltaic Solar Energy Conference and Exhibition which was held in Valencia. They exhibited a cell with increased efficiencies. It was not the highest efficiency recorded, but they were improvements which could be made using current production techniques. This is essential if they are to be able to be mass produced quickly.
They are therefore making sure that all of their advances can be applied to existing technology. They have set themselves certain targets which lead up to 2020. This is an important date as this is when the amount of energy produced by renewable sources is supposed to reach 20%. We are still a long way off that at the moment, but with each increase in efficiency the attractiveness of solar energy increases. To be able to achieve this the cost of production is also going to have to stay low, which is why it is so crucial that improvements are made that can be executed modifying current production techniques.
One example of an improvement they have made to solar cells is making contacts, which are currently silver screen printed, that are instead copper plated contacts. This has two benefits, firstly increasing efficiency, and secondly lowering costs. Copper is obviously cheaper than silver. In order to improve the texture of a cell, they have also come up with a laser ablation technique, and they have also developed a rear-side passivation technique.
At the moment, the efficiency of a silicon solar cell stands at about 19%, but that is not as bad as it sounds as the theoretical maximum possible is about 30%. The maximum actually achieved for silicon cells is about 25% but the only ones capable of doing this are too small to be manufactured for normal usage. For silicon cells of a large area, 20% is good and this is what is being aimed for by IMEC.
These are obviously not the cutting edge advancements in solar cell technology. However at the moment they are the most practical and will be soon a lot sooner than nanotechnology inventions. The modifications will be made relatively easily at production lines, and relatively quickly.
This is a great time to get involved in solar energy. Savings will be made to your electricity bill and to carbon dioxide emissions. The level of uptake in the UK of solar energy technology continues to increase.