The Innovation Lab: Storing the Sun
By Jeremy Turner, President of RPX
The ability to store the sun may seem like a lofty idea, but it is a real and critical aspect to the future of renewable energy. Energy storage, including battery storage, allows for the energy generated from a renewable energy source to be stored until it is needed. If there’s no storage, there is a definite limit to what renewables, like solar, can achieve. RPX, the new research and development division of ReNew Petra, is focused on bringing innovation to the renewable energy industry through crucial technologies like battery storage.
Energy storage can be seen as the final piece to making renewable energy a leading source of power generation. Storage allows companies to turn intermittent power into firm power. Currently, most renewable energy sources are intermittent, forcing utilities to continue their reliance on firm power generators like coal and nuclear. But energy storage would allow utilities the flexibility to transition from dirty, traditional energy and increase the use of clean, renewable energy.
Energy storage will also solve the problem of “peaker plants”; inefficient, traditional power plants that generally run only when there is a high demand. Energy demand tends to peak at specific times, however, those tend to be the same times that renewable energy supply drops. Because of this, utilities require peaker plants to meet that demand. But if we can store the excess supply of renewable energy when it is generated, it can be deployed for peak use.
There are several different types of battery storage currently being used and developed, including:
- Lithium Ion: Lithium ion batteries are the most widely used type of energy storage today. However, the major drawback to lithium batteries is that they do not allow for the full capacity of the battery to be used at one time. Although lithium batteries are relatively new, they are by far the most readily financeable. According to Bloomberg New Energy Finance, the prices of lithium ion batteries have declined by 80 percent since 2010.
- Flow: Flow batteries offer greater flexibility than other battery types. Flow batteries are composed of a liquid-based redox flow with large storage capacity. Redox flow refers to chemical reactions in the liquid solutions which flow through the battery to store energy. They also have a long service life and better operational resilience. This technology can be much cheaper than lithium ion, but still requires a substantial manufacturing scale increase to achieve cost efficiencies. Another drawback to flow batteries is the inability to transport them once they are installed given their bulky size.
- Lead-Acid: Lead-acid batteries are another widely used type of battery, used mostly as automotive batteries. A primary benefit to lead-acid batteries is that they have the lowest upfront cost, have a long history in battery storage, largely made from recycled lead, and are highly recyclable. As the need for utility energy storage has increased, so has use of lead-acid batteries for this purpose. However, lead-acid batteries need to be handled with care given the acid it uses and require regular upkeep to maintain required water ratio.New lead-acid batteries are being developed that could offer greater resilience and energy density that could make this technology a more viable option for utility scale energy storage.
According to U.S. Energy Information Administration, wind and solar energy accounted for less than 10 percent of energy generation in the U.S. in 2018. If storage can be utilized on all renewable production, then the likelihood for renewable energy overtaking traditional forms of generation increases dramatically. What’s more, as we see more growth in the solar market, we require similar growth in storage, and vis-a-versa
So why is it taking so long for this technology to scale up? Mainly, there has not yet been a battery or storage technology solution that is cost effective and viable enough at the scale required. In other words, an innovative idea to solve this has not been discovered. Yet.