Sunday June 12th 2011


Solar power will take over soon

The sunlight that hits earth in one hour is enough to cover the worlds energy demand for well over a year.

The surface of the Earth receives an amount of solar energy equivalent to roughly 10 000 times the worlds energy demand. Of course there isn’t always sunlight, but the solar panels can store the energy, and they are getting better and better at it. A solar panel converts one sixth of the sunlight into electrical energy. Although they also are getting able to turn more and more of the sunlight into energy, they are already so efficient that space isn’t much of an issue anymore. The area of solar cells needed to supply a family with electricity is usually much smaller than the roof of their house. And when including the land required for mining and excavation of coal, CPS-plants (power-plants that rely on solar energy) are more space-efficient than power-plants fueled by coal. Solar power is roughly fifty times as space-efficient as growing crops for bio fuels. And that’s just with the technology that currently is commercialized.

The clip bellow shows the best parts of the documentary Here comes the sun and is well worth taking a look at: reports:

According to the Energy Information Administration, in 1956 solar PV panels were $300 per watt, and in 1980, the average cost per solar modules was $27/watt and has fallen precipitously to approximately $2/watt in October 2009.

New breakthroughs point towards much cheaper solar panels in the near future (examples of this can be read about here, here or here), and with the emergence of nanotechnology, which already is underway, it’s reasonable to expect many new breakthroughs. But exactly when will solar energy become cheaper than conventional energy?

Solar cells are getting more and more efficient. The graph shows the best research-cell efficiencies for different types of solar cells measured in how much of the sunlight they can convert into electricity.

Ray Kurzweil, a famous inventor and futurists, predicts that this will happen within 2013. Dispatches from the Frozen North, a blog by the Peter Leppik, makes a calculation that leads him to think that in Minneapolis solar panels will be cheaper than power from the electric company in 2015, give or take a few years. Solarcentury, the UK’s largest solar company, predicts that in Britain solar energy will become cheaper or as cheap as conventional nonrenewable electricity by 2013. These are all uncertain predictions, and when it will become cheaper for you depends on where you live. But as far as I know most experts think that solar power will become cheaper than conventional energy in the near future – probably before 2020. And after that it will continue to become cheaper and cheaper. It’s a question of time before solar energy will be half the price of fossil fuels, one fifth the price, one tenth the price, etc.

Needless to say cheap solar energy will not just be good for the environment, but will also give other enormous benefits to society. And in many ways it will be more convenient than power from the grid. We will have to transport the energy less, and mobile phones, laptops, electric cars, etc. will be able to reload their batteries when they are outside in daylight. Another great thing about solar power is that it can provide cheap electricity to poor countries (in sub-Saharan Africa, etc.) where the power supply is unreliable and many villages aren’t connected to an electric grid.

Earths city lights at night. Cheap solar power can help light up poor parts of the world, where many villages aren’t connected to a grid.

Making solar power cheaper and more convenient isn’t just about getting better at converting sunlight into electricity. Storing the energy is also a part of the challenge. Breakthroughs are underway in this area (examples of this can be found here and here), and batteries are generally getting better, so there is reason to be fairly optimistic. That being said, the future of solar energy would be very, very bright even if energy-storing technology didn’t get better at all.

Despite of being fantastic in a lot of ways, cheap solar energy isn’t enough by itself to completely solve the energy-problem. We also have to make sure that fueling your car on solar power is cheaper and easier than using gasoline. Although maybe not within the run of this decade, I also think that electric cars will dominate the roads sooner then we think. But this post is long enough already, so I will save that for a later update.

Also published on

This article was originally posted on the Green Blog under a Attribution-Noncommercial-Share Alike license.