compression if the charging flow rate is equal to or less than the free flow rate from the reservoir. At peak times, the high flow rate from the CEGS system can be combined with the free flow rate from the depleted oil or gas-type gas storage reservoir, again saving compression power. Performance varies with energy ratio (ER). This is defined as electric energy output divided by the electric energy required to produce the stored LNG (and heat the molten salt). The ER can be adjusted by changing certain operating parameters of the cycle. These parameters can be adjusted depending on various factors: the cost of fuel; cost of excess stored electric energy; revenue from the produced electric energy; the value of moving the gas from off- peak to peak time; and whether there is a payment for the ability to deliver gas at a high flow rate at peak times. The ER range shown in Table 1 would be for typical operation; however, in emergency situations (such as many days of clouds and low wind), the system can produce full peak-time power and move the full amount of gas from off-peak to peak time without consuming any electric energy. The fuel rate in this mode would be approximately 7,200 BTU/kW-hr, still much better than a peaking gas turbine. Removing the storage roadblock The progress of renewable generation has been spectacular in recent years. But it will hit a dead end unless the storage challenge is surmounted. Most investment has been in battery energy storage systems. Attention now needs to be paid to long-duration options. Pipeline companies, gas storage operators, utilities, renewable energy project developers, and LNG sites are in a position to lead the way in long-duration energy storage. With North America and Europe having such well-developed pipeline systems and so many LNG import and export terminals both in existence and coming online soon, the economics of long-term storage can be improved by combining the storage of excess renewable energy and natural gas.
Meet GEA mobile CO 2 separation units.
Capturing carbon dioxide before it enters the atmosphere is critical for emissions and greenhouse effect reduction. GEA offers small & medium-sized CO 2 capture plants for various applications, suitable for a wide range of inlet conditions and exhaust gast compositions.
Meet us at the Carbon Capture Technology Expo. Bremen, Sept. 27 th & 28 th .
VIEW REFERENCES
Jim Berry berryjx@gmail.com
www.decarbonisationtechnology.com
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