Document Type

Closed Project

Publication Date

Spring 2019


Judith Estep

Course Title

Energy Technology Innovation

Course Number

ETM 568


Electric power systems -- United States, Electric power distribution, Energy storage -- Technological innovations, Smart power grids


The electric grid is a complex and critical piece of infrastructure that requires constant balancing. At any given moment, supply and demand must be equal to one another to maintain the delicate balance and ensure continued operation. Adjustments are always made when a spike in demand occurs or when there’s an oversupply of production. During spikes of demand more power needs to be produced, and fed into the grid, and when demand drops of a scenario where too much power is being produced, plants need to be curtailed.

In the United States, utilities traditionally operate and maintain peaking power plants specifically for times when demand spikes. The majority of these plants use fossil fuels to produce energy, and by extension produce carbon dioxide emissions in the process. As states enact increasingly ambitious renewable power standards, or enact cap and trade policies, utilities will have to build additional generation sources that produce their energy from renewable sources like solar or wind power, and drive towards decarbonization.

Energy storage could be a technology that addresses both the decarbonization of power generation and the inherent challenges that solar and wind power face. First, solar power installations like photovoltaic (PV)solar panels only produce power during daylight, so a battery or energy storage solution paired with solar could potentially feed power into the grid when the sun goes down. Second, wind speed tends to be higher and more consistent at night, when electricity demand is low. A wind farm with an installed energy storage solution could store energy for the following days peak, and could supplement or replace a peaker plant entirely, while a PV installation could store energy before peak use time, when the sun is out.

As the grid continues to be modernized towards a “smart-grid” future, energy storage could harness the power of renewable energy both on the utility side as well as with distributed generation sources such as rooftop solar, in behind the meter applications. As Katie Fehrenbacher of GigaOm once stated “A next-generation smart grid without energy storage is like a computer without a hard drive: severely limited” (Valimak, 2015). With that in mind, we set out to analyse three energy storage technologies, solid state batteries, flow batteries and pumped hydro using a PESTLE style analysis.


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