Make clean energy reliable
The intermittency of clean energy (primarily wind and solar) is a major hurdle to achieving aggressive clean energy targets and reducing reliance on fossil fuel generation. The General Compression Advanced Energy Storage (GCAES) system firms intermittent generation from conventional wind turbines and solar arrays by storing excess energy in periods of high wind or insolation or low demand and releasing it in periods of low wind or insolation or high demand. The excess energy is stored in the form of high-pressure air and warmed water. When the process is reversed, the high pressure air combines with the warmed water to deliver electricity. This fuel-free method of firming intermittent renewables generation helps make wind and solar energy more viable and cost-effective grid-scale generators, thus increasing their value.
Improve the utilization of generation and transmission assets
Generation capacity and transmission assets are built to meet peak day demand requirements with a reasonable reserve margin, resulting in an underutilized electric supply system. On a global basis, generation resources operate at a capacity factor below 50%. GCAES enables grid operators and power off-takers to dispatch energy generated during lower demand off-peak hours for storage, then release that stored energy during peak periods. This increases the utilization of existing generators and transmission facilities, allowing operation at optimal performance points substantially more often, while still meeting the significant variable end-use demand for electricity.
Allow base-load plants to be load following
Globally, many markets do not have ready access to natural gas or other low cost fuel supplies in sufficient volumes to meet new generation requirements. Some of these markets are focused on increasing renewable energy, while others have a broader strategy that includes new nuclear and clean coal. In addition to the intermittency of renewables, nuclear and clean coal plants provide material challenges for grid operators and off-takers due to their inflexible operating profiles. Limitations in how quickly these generators can ramp up or down lead to material inefficiencies and cost increases to consumers. GCAES enables grid operators to cycle nuclear and other base-load generation assets by storing power during off-peak hours for redelivery during on-peak hours, improving the performance of those assets, increasing their value, and reducing the need for new expensive on-peak capacity.
Improve the efficiency of the grid
The lack of electricity storage on the grid requires operators to maintain or contract for spinning reserves and ancillary services necessary to respond to demand changes and grid requirements. Underutilized generation capacity must be kept in service, and in some cases online and ready for load, to meet peak demand. In markets with aggressive renewable targets, grid operators struggle to integrate wind generation, particularly during high wind off-peak hours. GCAES can reduce the need for (and thus the cost of) spinning reserves and ancillary services to provide ramp-up, ramp-down, capacity or other grid needs. By storing off-peak wind energy during periods of lower demand, peaking needs can be met more cost-effectively. Grid storage enabled by GCAES can reduce inefficiencies, increasing the value of infrastructure while reducing the total cost of operation.