According to a new report from the Energy Information Administration (EIA), the use of renewables, including solar, wind, and geothermal, is estimated to nearly double by the year 2040. The same report also estimates that the use of natural gas, currently the biggest competitor to coal, will grow by 56% over the same time period. The EIA’s report reflects global energy usage, not just the United States’ or any one country. So though renewables are projected to grow by 97%, it will still amount to less than 4% of global energy production.

An array of solar panels being installed on a US naval base

An array of solar panels being installed on a US naval base

However, the EIA’s projections are considered to be more conservative than estimates from other institutions as their figures only incorporate current adoption trends. The administration’s report does not take into account advances in the efficiency of renewable technologies, as well as improvements in energy storage. Photovoltaic cells currently on the market generally achieve efficiencies of only 35%, meaning they convert only 35% of the energy they receive from the sun into electricity. Several research teams around the world are developing solar panels that could potentially reach 80% efficiency, with one group recently announcing a new solar cell with 44.7% efficiency.

But efficiency is only one obstacle holding back the rapid growth of renewable technology. Since renewables rely on unpredictable natural processes, such as sunlight and wind, they often produce energy when it is not needed. In order to fully harness the potential of renewables, newer energy systems are needed to store electricity during off-peak hours so that it can be reused at night when energy demand skyrockets. Fortunately, companies like Solar City have already started rolling out lithium-ion battery storage systems for businesses with solar panel installations.

These units allow excess energy produced by solar installations to be stored within the batteries for later use. Utility-scale versions are currently in development both by Solar City and a number of their competitors. Installing battery storage systems will allow utility companies to save large amounts of electricity, getting around the problem of cloudy weather or days where the wind is lackluster.

There are also numerous improvements to battery technologies in the pipeline that promise to significantly increase storage capacity. One such example includes a new breed of batteries that rely on the reaction between lithium-ions and oxygen atoms to store energy in densities that rival gasoline. Replacing traditional lithium-ions with lithium-oxygen cells would allow electric cars to drive as far as gas-propelled cars, as well as allowing renewable energy systems to store enough energy to rival fossil fuels.

Even if the future of renewables is more in line with the EIA’s predictions, they will continue to play a significant role in a world where fossil fuels have a finite supply.

For more information on the state of solar power, check out the Solar Action Alliance’s blog.

Source: The Week