We often get asked how technology in the solar industry is developing, and the answer surprises a lot of people. Yes, the efficiency of solar panels continues to improve bit by bit, but the biggest and most important improvements are in cleaning up the manufacturing process and making solar panels more environmentally friendly.
As an example, the amount of silicon required for a standard 60 cell panel has decreased from 16 grams/Wp to only 6 grams/Wp due to thinner wafers and new technology. But as the saying goes; “it takes money to make money”, it also costs energy to make solar panels.
The term energy payback attempts to measure this idea. Essentially, how long does a solar panel have to be in operation for it to produce enough energy to pay back the energy (and associated pollution) it took to make the panel?
The answer surprises a lot of people because the energy payback of a solar panel is now between 0.5 years and 1.4 years for most of the big brands being sold in Australia. This is well below what most people expect – and given that they have an expected life of decades, is a pretty good deal for the environment.
Many of the cheaper solar panels still use quite toxic chemicals and heavy metals in their manufacturing process, which is just one more reason to stay away from this end of the market. But for the better brands such as the ones Solaray stock, the main variance that determines a panel’s energy payback is where in the world it is installed.
For example, here in Sydney where solar power is well-suited, the energy payback is much shorter than 1 year. In countries where solar systems output less power such as England, the energy payback is more like 1.5 years, simply because the panels aren’t producing as much power to pay back their embodied energy.
All in all, solar power is looking more and more like the way of the future.
If you are interested in further information, this Fraunhofer Report has a great summary of their European based research.