According to new research by the MIT Energy Initiative, hydrogen will be a viable source of backup power for renewable sources like wind and solar (MITei).
As variable and intermittent renewables account for a rising percentage of power generation, power storage and backup generation will become increasingly essential in supplying backup peaking power. According to TechXplore, MIT researchers carried out a technical and economic analysis of power supply choices for the California grid, including lithium-ion batteries, green hydrogen, and blue hydrogen.
The study calculated the levelized cost of energy (LCOE) of several backup solutions, such as converting existing natural gas-fired power plants to hydrogen to satisfy peak electricity demand. “Hydrogen can be a more cost-effective alternative to lithium-ion batteries for peaking operations on a power grid,” said Emre Gençer, an MIT research scientist and co-author of the paper.
“If hydrogen has a place in the situations we looked at, that implies hydrogen has a potential role to play in the energy transition” to a decarbonized power system, according to Gençer.
Green hydrogen produced by electrolysis would be cheaper than lithium-ion battery storage, which costs $3,000 per megawatt-hour. At $1,560 per MWh, blue hydrogen generated from fossil fuel feedstock would be even cheaper. However, there are “concerns concerning the availability of blue hydrogen and the lower carbon benefit as compared to green hydrogen,” according to scientists.
Backup power is needed in centralized power networks to compensate for short-term disruptions in renewable output, such as a lack of wind or sun for several hours. Longer shortages, such as poor hydropower output during a heatwave with a high cooling load, necessitate backup. According to the study, lithium-ion battery storage is more suitable for short-term rather than long-term generation shortages.
The authors acknowledge the economic and political difficulties of scaling up hydrogen production for peaking power, including the requirement for substantially higher energy pricing that reflects carbon costs. Converting natural gas plants to hydrogen is expensive, and conversions are unlikely until a hydrogen energy infrastructure for other applications, such as industry and transportation, is created.
Industry proponents have hailed blue hydrogen as a way to reduce pollution. However, according to a recent study by Cornell University’s Robert Howarth, generating hydrogen from natural gas with carbon capture has a 20% greater greenhouse gas footprint than just burning gas or oil for heat. The release of fugitive emissions of methane, which is roughly 80 times more powerful than CO2 over a 20-year period, is a key and frequently ignored the issue. Furthermore, the researchers point out that industry claims of permanent carbon storage are “optimistic and untested.”
Hydrogen is a highly combustible and low-density gas, which adds to the difficulty of transporting it from the source to the end-user.