How are we going to power the future? Energy is a huge concern, so lets examine recent advances in solar energy. It is difficult to discuss energy generation (solar in particular) without hearing the same tired objections. Therefore, a little myth busting is in order:
Myth 1: Solar power is not abundant enough to power the world.
False. As the article notes, everything on earth consumes something like 15,000 gigawatts (GW) of power. However, the Earth absorbs something like 89 petawatts (PW) of solar energy on the surface (and about twice that in the atmosphere.) Since a single PW equals 1,000,000 GW, that means if we can collect a mere .00017% of the solar energy that hits the Earth we will have enough energy to power all of Earth’s needs for an entire year. The idea that there is not enough solar power to power the world is not just wrong, it is ludicrous. We are swimming in energy; energy that is clean, renewable, and abundant.
Myth 2: Solar panels are not efficient enough to power our needs.
Half-true. Despite how much solar power is bombarding the Earth at any given moment, solar is currently just less than twice as expensive as fossil fuels. However, two trends need to be kept in mind: fossil fuels are getting more expensive (and their polluting costs are not factored into their costs to buy at the home) and solar panels are getting both cheaper and more efficient. Thus, solar energy could power 10% of the Earth’s needs as early as 2018 and, as it follows the exponential growth model, would reach 100% of the Earth’s needs less than four doublings later (or about 72 months, given the usual 18-month doubling time.) That means that by 2024 everything on Earth could be solar-powered, and for much cheaper than fossil fuels.
We are already seeing progress in making solar panels that are more efficient. Scientists at Cambridge have developed a cell that can capture up to 44% of the solar energy that hits the cell, meaning that a one square meter cell could create an average 3 KW per day, or 1095 KW/year. A typical American home uses about 11,500 KW/year, so the typical American home would need roughly eleven square meters of the new solar panels to power their home for a year. Desert climates would need less (especially during summer – about half) while northern climates like Seattle during winter would need more.
However, the news is better than that. The above assumed a single, flat solar cell one square meter in size. A more efficiently stacked solar panel array, like this one proposed by MIT, produces from two to twenty times more power. That means that the typical American home would need five square meters of space or less to power their home for a year (and probably create excess power.) Installation costs are the largest barrier to solar installation, but this could be quickly recouped with no power bill (or a source of income for those states that allow consumers to sell their power back to the grid.) Further, with such small spaces needed for power, there ought not to be much need for a grid at all; saving everyone money in the form of taxes paid for infrastructure.
However, not all power would need to be generated by solar panel structures like those linked above.
Northwestern University has created printable window tint that converts power to electricity and it could be cheaply applied to existing flat panel windows (including those on electronic cars.) While the conversion rate is not as good as the new cells by MIT, if used in conjunction with a standing cell array the power generated by window tint cells is just icing on the cake. In line with the expected innovative explosion following an exponential curve, other companies are already working on similar technologies. This German company, for instance, has a similar product on the way to launch.
While on-site electricity generation is very exciting, Spain has recently debuted a solar station that gathers 1,000 times more solar energy than usually hits the Earth’s surface and even works at night.
Similar stations could provide any additional power needed while the efficiency of home models catches up, and the technology could scale down to further improve home electricity production. All of these innovations together make California’s stated goal of net-zero energy usage for housing by 2020 seem plausible. For one more example of solar innovation, this ship has been sailing at sea for over two years without a drop of oil – and using solar technology several generations behind these cutting edge innovations!
Image 1: Stacked solar panel designed by MIT.
Image 2: Solar energy station in Spain.
Image 3: Solar powered catamaran.
IEET Blog
In cold and cloudy climates, solar power is still a good option if you choose the right technology. For instance, I live in Canada and my house is equipped with glycol pipes in solar panels. Instead of trying to produce electricity with photovoltaic cells, heated glycol fluid is used to transfer heat to my water heater. It’s very efficient.
As for photovoltaic cells, there is a HUGE market for indoor applications. For instance, most of our battery-powered objects in the house should have small solar panels: wall clock, smoke detector, night lights, etc. We could also embed flexible solar panels into curtains or window shades, and rigid panels into floor tiles (especially in front of patio doors).