Considered a large-scale water battery, pumped storage hydropower is poised to play an important role in the clean energy transition. Already, existing fixed-speed pumped storage hydro represents 93% of all grid-scale storage in the U.S. These facilities are already shifting operations to better accommodate wind 和 solar.
55千兆瓦的大部分 新 pumped storage hydro projects in development will utilize variable speed turbines, meaning they can shift speeds in pumping 和 generating mode, offering lots more value to a zero-carbon grid that will be starved for stability.
- But exactly how much value can variable speed pumped storage hydro provide under many grid scenarios?
- 价值流从何而来? And what factors could affect this value?
To answer these questions, I turned to the results of a recent study, commissioned by the U.S. Department of Energy 和 conducted by GE. The researchers used two case studies to examine these questions 和 puts some analytical rigor behind the claim that pumped storage hydropower will be highly valuable in a low-carbon grid.
该片将于2021年10月上映 清洁洋流会议+贸易展这份报告, Value 和 Role of 抽水蓄能 Hydro Under High Variable Re新ables, paints a convincing picture of pumped storage hydro’s future. The report focuses on two proposed projects in the western interconnect: 大的斜纹棉布裤, a 2,000-MW closed-loop project outside of Phoenix 和 San Vicente, a 500-MW project outside of San Diego.
GE团队模拟了WECC, 西方的网格, under various re新able 和 storage deployments in the year 2028.
What’s the Value of these Two Projects to the Western Grid?
Using an innovative price maker model rather than a less rigorous price taker model (these plants are large so their participation in the market alone will shift pricing), the GE team found that the plants reduced production costs by $244 million.
Under this base case of 50% re新ables, 更少的电池, CO2 emissions were reduced by over 2 million tons in addition to lowering curtailments of wind 和 solar as well as reduced cycling from the thermal plants.
While the system benefit of pumped storage hydro under a 50% re新able case is clear (see above), what does this mean in dollar 和 cents for the developers?
Figure 2 from the report shows the various operating profits for both 大的斜纹棉布裤 和 San Vicente in the year 2028. Most of the revenue comes from the energy market (Arizona 和 California don’t have central capacity markets) followed by operating reserves 和 then spinning reserve revenues.
Profits are largest in low hydro years 和 are lowest in lower re新able buildout scenarios coupled with wet hydro years. 在所有情况下, developers will experience lower profits in high battery storage scenarios 和 higher profits in scenarios assuming lower battery buildouts. (请参见报告中的图6.)
What Factors Most Affect the Value of 抽水蓄能 Hydro?
一个有趣的发现, the GE team concluded that pumped storage hydro is not competing against shorter duration batteries. Instead, the largest competitor for pumped storage hydro is … more pumped storage.
很明显, this might change if one of the emerging (but not yet commercial) technologies for longer duration storage becomes cost effective. 然而, GE found that the two largest variables affecting pumped storage hydro value are re新able penetration (the larger the share of re新ables, the greater the pumped storage hydro value) 和 the volume of total energy storage (meaning other long duration technologies).
There is LOT more great analysis in this report, Value 和 Role of 抽水蓄能 Hydro Under High Variable Re新ables including a 新 scheduling tool for variable speed pumped storage hydropower.