America’s electricity generation is heavily dependent on coal and natural gas, both of which contribute to the already massive amount of emissions present in the world.
Intuitively, one would think that the fix to this problem is renewable energy. This is correct. But, in order to make this solution truly effective, there’s something else we need to give attention to: renewable energy storage.
The woes of renewable energy
In a recent article from Nature, investing in energy storage technology was shown to have a key role in deeply decarbonizing electricity production. In the US, there is a conscious shift to renewable sources. This is made easier by the lowering cost of building infrastructure for renewable energy.
As a matter of fact, renewable energy sources momentarily surpassed coal in electricity generation last April. However, we still have a long way to go. The downfall of energy sources such as hydroelectric dams and solar panels is the storage of the energy produced.
Contrary to what most would think, renewable energy sources — hydroelectric, solar, and wind — actually provide an oversupply of power needed. The problem is, our renewable storage mechanisms are underdeveloped. With this, much of the energy produced by renewable energy sources actually to waste.
In their study, Nature built a model which examined nine existing energy storage technologies:
- pumped-hydroelectric storage (PHS),
- adiabatic compressed air energy storage (ACAES),
- Diabatic compressed air energy storage (DCAES),
- lead-acid (PbA) batteries,
- vanadium-redox batteries (VRB),
- lithium-ion (Li-ion) batteries,
- sodium-sulfur batteries (NaS),
- polysulfide bromide batteries(PSB), and
- zinc-bromine (ZNBR) batteries
The model takes into account the power and energy capacities of the energy storage technology as well as the power system operations.
By doing this, the total system costs are minimized. Total systems costs can be broken down to:
- capital cost of energy storage,
- generator-operations costs, and
- CO2-emissions costs
Using case studies in California and Texas, here are some of the important figures:
- California: Without energy storage, a 60 GW deployment level of renewables achieves 72% worth of CO2 reductions. Energy storage technologies can raise it to as high as 90%.
- Texas: The same level of deployment leads to 54% reduction in carbon emissions. Adding energy storage tech into the mix and this increases to 57%.
Here are also some findings also resulting from the same study:
- renewable curtailment and CO2 reductions depend on the capital cost of the particular energy storage technology
- PHS and DCAES are typically deployed due to lower capital costs
- increasing the CO2 tax makes energy storage more cost-effective.
Some nudging required
With this, we see that there is a need for companies to invest in the innovation and strengthening of renewable energy storage systems.
Given the high capital cost, some push from our leaders may be needed. For instance, by increasing the carbon tax, energy companies will be enticed to spend more on developing these technologies.