Is methanol a new type of energy storage

Can methanol be used as a cyclic energy source?

Upcycling carbon dioxide (CO 2) and intermittently generated renewable hydrogen to stored products such as methanol (MeOH) allows the cyclic use of carbon and addresses the challenges of storage energy density, size and transportability as well as responsiveness to energy production and demand better than most storage alternatives.

Could methanol be an alternative to hydrogen storage?

Methanol as ULDES could offer an alternative to hydrogen storage. A concept for methanol storage with carbon cycling from Baak et al. 8 is sketched in Figure 1 with all inputs and outputs. Methanol can be synthesized from electrolytic hydrogen and carbon oxides (so called “e-methanol”).

Can methanol be used as an energy storage medium?

As an energy storage medium, methanol displays high performance as an additive or substitute for gasoline in internal combustion engines. The direct conversion of the chemical energy in methanol to electrical power at ambient temperature has been demonstrated in methanol fuel cells (McGrath et al., 2004).

How is methanol stored?

Methanol is stored as a liquid at ambient temperature and pressure, oxygen is stored as a liquid at - 183 ∘ C, and carbon dioxide is stored as a liquid at 7 bar and - 50 ∘ C; only hydrogen is stored as a gas (at 250 bar) while it is buffered before going into the methanol synthesis. Figure inspired by Baak et al. 8

Is methanol a cost-effective solution?

Since using the methanol system is still 29%–43% lower in cost than using aboveground pressure vessels for hydrogen, it presents the most cost-effective solution of those studied here where salt deposits are not accessible. The round-trip efficiency for hydrogen storage at 38% is higher than for methanol storage with carbon cycling at 35%.

Does methanol synthesis require large-scale hydrogen storage?

In production facilities using fossil fuels, methanol synthesis is run with high-capacity factors. Maintaining these high load levels with fluctuating hydrogen supply from variable electricity would require large-scale hydrogen storage to buffer the hydrogen, which may not be available as discussed above.