A solar PV system is a system that directly converts the suns light into electrical energy. This electricity can then be fed into the electrical system of the house, office or factory where it can be used on it’s own, or in conjunction with the main electrical supply. Solar PV can therefore directly reduce or remove the electrical costs of the user. In some cases electricity can even be exported by larger solar PV systems onto the electricity grid, providing a source of income.
The science bit
The PV panels are positioned so that maximum light will shine upon them over the course of the day. Light which hits the panel, passes directly through the glass plate, found on the surface of the panel, and into the silicon layer of the panel. The energy from the light excites electrons within the silicon semiconductor layer of the panel, creating an electrical current. This current is then passed through a piece of electrical switch gear called an inverter, before going on to the main fuse board. The inverter converts the current from DC (like in a battery) to AC (like in a house). From this point the electricity supply the needs of the building. If the demand is too great, electricity from the main electricity supply can combine with it to provide for the demand. If it is too little the electricity can charge a battery, or be fed onto the national grid. As there is no sun light at night, a large battery would be required to keep a supply over the course of the night.
So… Do they work?
In comparison to other renewable technologies, solar PV panels are relatively immature. Most experts believe that PV would be the ideal solution to the worlds energy problems. The sun shines every day, they are relatively unobtrusive, they can be put in the places where energy is being consumed. The problem is, that for their cost, they can’t compete with other technologies. At the moment solar PV is primarily used on road signs and remote installations, places where the cost of running an electric cable is prohibitive, but for generating electricity for your home, the other technologies win out.
NOTE: Technology is moving forward fast… don’t give up on it just yet. Check out this site for an ongoingcommentary
greennav
martinfaulkner
micallc
thenewoil
ciablasar
March 26, 2008 at 1:36 pm |
One of the things that strikes me about a household set-ups like the one above is the use of an inverter. As I look around me I see rectifiers that turn AC back to DC, my laptop my cellphone charger, computers etc. It seems to me that there would be some case to be made for installing a DC circuit in your house. It would be interesting to see would removing the combined inefficiencies of the inverter and rectifiers in the about set up lead to a more cost effective system. For instance I know my laptop powers supply is inefficient because of the amount of heat it generates, you could fry an egg on it!
In addition DC lighting and other services are well proven in boats and trucks.
Daniel
March 26, 2008 at 2:14 pm |
Hi Daniel, thanks for the comment. I think the problem is the lack of a standard. In from of me is my laptop charger and a phone charger. One is 19V and the other is 5V. So you would still need loads of transformers for your different bits of kit.
Also I think there are issues with resistance in electric wire and overheating and houses buring down and the like… but you’d have to ask a real electrical engineer for that one.
I think it will be an interesting one for the future though.
June 5, 2008 at 8:56 pm |
I feel very similar on this topic but have some new ideas also. I will start a new thrread.
January 7, 2009 at 9:43 pm |
[...] an export tariff to domestic home owners. So the idea is that if you install a Wind turbine, a Solar PV panel, or a Micro-CHP, you will be in a position to sell electricity to back to the grid for profit. The [...]
October 3, 2009 at 7:26 pm |
best pv panel…
A solar PV system is a system that directly converts the suns light into electrical energy. This ele [...]…