So last time, we talked about wind power, its ups and downs, its recent innovations, and how Americans are incorporating it into their energy infrastructure. It remains very viable yet still slightly cost ineffective. Today, we are going to talk about a type of clean, renewable energy quite similar in nature to wind power: solar power. Now, I know, light from the sun and the wind have very little in common when you’re standing outside, however both forms of energy share similar benefits and drawbacks.

Before we delve into the pros and cons of adopting solar power, we should first talk about what it is exactly so we can better discuss innovations in the field. Solar generators basically come in two flavors: photovoltaic cells and concentrated solar power (CSP). Photovoltaic cells directly convert photons (light particles) from the sun into electrons to flow as electricity. This sounds too good to be true! Light from the sun goes directly into the wires that power all our machines and devices. Unfortunately, that’s not quite the case. The best efficiency currently achieved is about 20% conversion.  That is to say that only about 20% of the energy from the sun makes it into the grid. Also, these cells use silicon which is facing a shortage.

CSP works more like a traditional power plant. The solar powers actually focus, concentrate, and reflect solar energy into a vessel of fluid. The energy boils the fluid and generates electricity via a steam turbine.

All forms of solar energy fall victim to several drawbacks, with the main one resembling wind power. Its not always sunny. Solar farms obviously don’t work when the sun isn’t shining, whether on a cloudy day or at night. Plus, you need a large area of solar farms to generate significant power. According to the Institute for Energy Research, an area the size of  New Hampshire and Rhode Island would be needed to power the US. When you need to transport this power over large distances, some power is lost in transit. Combine all this with the current cost-prohibition, the US sees only 0.2% of its utility power generation from solar.

For more from the Institute of Energy Research, click on the pic.

Nevertheless, solar power has several key benefits over traditional fossil fuels: no waste, no pollution, and no input consumables since all the energy comes from the sun.

And thankfully, there are the faithful innovators out there trying to make this power more efficient and cost-effective for the rest of us to reduce global climate change from fossil fuel consumption.

A promising new development is including other metals in the photovoltaic alloy such as titanium and vanadium. This would increase the absorbency into the infrared region and bump up efficiency by over 20%.

Another by CoolEarth is using cheap balloon concentrators to focus more light on to the photovoltaic cell. They claim its roughly four hundred times cheaper than traditional concentrators.

One of CoolEarth’s concentrating balloons.

Most of the other innovations I have found focus on reducing the cost of the panel itself. Some of these companies are printing the photovoltaic alloy on thin polymers to reduce materials. Some are spacing the expensive silicon materials apart to use less material. All these innovations and more (slightly technical ones) can be found here.

To finish up, I’m going to talk about an interesting innovation that could be stalled by congressional policy in the US. A Spanish energy company called Abengoa owns a massive solar farm in the Mojave Desert called Solana. The solar farm runs on the concentrated solar power method. However, it can do what few other solar farms can do. It can generate power after the sun goes down. As the sun reflects off the reflectors to heat the fluid, it also heats a large container of salt. This produces a stored molten salt that can hold heat to be used to generate power later. It’s basically a heat battery! However, due to uncertainty regarding a certain investment tax credit, the company has no plans of expanding this technology in the US. The tax credit is worth 30% of the project’s cost and there is currently “momentum” in Congress for eliminating renewable tax credits with Republicans against renewables and Democrats against fossil fuels. With so much stagnation and uncertainty, companies aren’t interested in investing. Read more about the issue here.

A solar farm in the Mojave Desert.

So what do you guys think, should Congress push through these tax credits to get more companies on board, or is solar technology not worth the time as a renewable? Let me know below!