Most people today have come to rely on their local power company to provide electricity to their homes. While this form of electricity distribution is highly efficient and stable, most people have no backup plan for when the local power company fails.
Moving from the current grid power model to a more distributed model would ease our dependence on “dirty” fuels like coal. It would also save individual homeowners money and provide a more stable power supply in the long run. Many green energy systems can also connect to the power grid for sharing excess energy with the rest of the community, and perhaps getting a rebate from your power company.
How Electricity is Generated
I am not an expert in electricity, so there may be some inaccuracies in what I write here (let me know in the comments), but here is my understanding of how electricity is generated. Most electricity today is generated using turbines. Basically, an electricity-generating turbine consists of a magnet and a metal coil. When you spin the metal coil, electricity is generated. Therefore, if you can get something to spin the turbine, you can generate electricity from it.
Water power uses moving water to spin turbines (that’s why waterfalls are excellent locations for water power). Wind power is generated by a windmill spinning a turbine. Coal power is generated by burning coal to boil water, causing steam to rise and spin turbines. Nuclear power works the same way, using nuclear fission to boil water and spin turbines with the steam.
Another type of electricity generation that is rising in popularity is photo-voltaic power generation. This is using sunlight to generate electricity. We’ll discuss this first.
Solar Power
Our current technology for harvesting solar power is photo-voltaic cells. Most solar panels are about 11-15% efficient. While that looks very inefficient, the encouraging news is that it leaves a lot of room for improvement.
Solar panels are typically mounted on roofs. It typically costs a little over $10,000 to install on your home after incentives. One company currently installing solar power for homes in the United States is SolarCity.
Wind Power
Solar panels aren’t the only thing that you can install on your roof for generating electricity. Small wind turbines can also be installed on a roof.
Wind turbines today take the form of a windmill installed away from the home. There are many challenges to installing one on the home itself, the main challenge likely being that the turbine must be at least 18 feet in diameter to be effective. However, perhaps it is possible to mount several smaller turbines on a roof. There might be a way to engineer them to automatically turn in the direction of the wind as well. Such turbines may be in the form of a windmill, or perhaps “wind tunnel” shafts with small turbines inside (and grates on the outside to keep animals out). Energy generated from these small wind turbines might be used to power a storage battery for auxiliary energy.
The problem with current residential wind turbines is that they are less efficient and stable than solar power. Most home rooftops simply aren’t very good locations for wind turbines. At least one startup in Denmark is working on a solution. Honeywell is another company working on small wind turbines.
What do you think? Do you know of other ways to generate energy from your rooftop? Any other solutions? Let me know in the comments.