One of the most popular forms of non-renewable energy has always been solar power, and why not? Its use emits few hazardous byproducts, obtains energy from something that won’t go away any time soon, and is comparatively non-invasive. So, why isn’t it widely used? The most significant flaw with solar power is with how inefficient the current technology is. According to Steve Byrnes from Forbes.com, the highest energy efficiency without a budget is roughly 35% from Spectrolab. This company offers unconcentrated photovoltaic (PV) cells of this efficiency for $100,000 per square meter. For the consumer on a budget, the efficiency is 20% from SunPower. That being said, solar power is not a complete loss. With all the reports made on finding superior methods and materials for creating solar panels, the chances for creating a future where solar power that’s as energy efficient as coal will be a reality.
One novel approach to creating new solar panels is to replace silicon with Perovskite, a method that was first unveiled in 2009. In conjunction with splitting water molecules into separate hydrogen and oxygen atoms, Perovskite solar cells have enough absorbed power to split the molecules with an efficiency of 17.3%. This was something that silicon-based cells could not accomplish alone, due to the lack of open circuit voltage. In other words, what one Perovskite cell can do must be done by a series of three silicon cells. As this new technology has great potential, it suffers from certain drawbacks. Perovskite cells are unstable and tend to break down over time. Over time and further development, these novel cells may become a more energy efficient means of producing solar power.
Another approach is the recently discovered method of using air-breathing lithium batteries with solar cells. According to Sebastian Anthony from ExtremeTech,
“The new device, developed by Ohio State University, is essentially an air-breathing lithium battery that recharges via a built-in solar cell. This is significant, because one of the biggest problems with wide-scale solar power deployment is that you also need huge banks of batteries to store electricity — to even out spikes in generation when it’s cloudy or dark – and not only are those batteries expensive, but a lot of electricity is lost simply by traveling from the solar panels to external storage. An integrated solution is both cheaper and more efficient — about 25% cheaper and 20% more efficient, according to the researchers.”
Despite this innovative device’s points on increased efficiency on both cost and energy, it has its shortcomings. For example, lithium batteries are expensive. Being an integral component to the device’s design, it cannot be replaced by a cheaper analog but the design can be improved. With the funding provided by the US Department of Energy, the performance of this design will be improved over time and may eventually become the default solar technology.
With all the efforts in artificial designs and conjectures, some are looking to nature for possible silicon replacements. Research has shown that giant mollusks, over 4 feet long, have the potential to create solar power. Certain mollusks, specifically giant clams, have special iridescent cells called iridocytes that reflect light into the shell’s interior. This would in turn allow symbiotic algae process the energy via photosynthesis, benefiting the clam. This process could be used as a means of generating solar power through biological means.
With all these developments in solar power technology, one could make estimate on when the technology will be made mainstream and consumer-friendly. According to reports from the International Energy Agency (IEA), solar power could be world’s largest source of energy by 2050. This is due to the rapid decline in module cost that has occurred in the last few years. “The rapid cost decrease of photovoltaic modules and systems in the last few years has opened new perspectives for using solar energy as a major source of electricity in the coming years and decades,” said IEA Executive Director Maria van der Hoeven. “However, both technologies are very capital intensive: almost all expenditures are made upfront. Lowering the cost of capital is thus of primary importance for achieving the vision in these road-maps.” These reports are not a definite forecast for things to come, but do offer insight as to the increasing interest in solar power. As solar technologies are maturing and becoming more energy and cost efficient, seeing a future filled with more solar panels than coal mines may become a possibility.