Apex Compressed Air Energy Storage, LLC

Apex is a Texas-based company created to develop, construct, own and operate compressed air energy storage (CAES) plants. CAES is a proven power storage and generation technology with unique capabilities advantageous to emerging grid and power market needs. Development and operation of our projects will adhere to Apex’s core values.

Values:

The Apex team is committed to making a positive contribution to the communities in which we work. Every decision we make is measured against our core values:

• Integrity – We adhere to the highest ethical standards in pursuit of our objectives
• Excellence – We hold ourselves to the highest standard of excellence in everything we do
• Innovation – We strive to lead the industry in project design, execution, and operations
• Balance – We account for all stakeholder interests – investors, customers, employees, surrounding communities, grid operators, and regulators

 Background:

Compressed air energy storage (CAES) is a proven and reliable energy storage technology unique in its ability to efficiently store and redeploy energy on a large scale, in order to provide low-cost energy and ancillary services.

During hours of low energy pricing

• Compressor – purchase electricity from the grid to run electric motor-driven compressors and pressurize air for storage in an underground cavern; compressor acts as the ultimate demand response provider – remaining available to reduce electricity use instantaneously
• Generator – run at LSL (low sustainable load) and provide large volume of valuable ancillary services or energy as system demands dictate

During hours of high energy pricing

• Compressed air is withdrawn from the cavern, heated, and introduced to one of several combustors
• In the combustors, natural gas is fired to further heat the air, and the hot, expanding gases are used to drive expansion turbines
• These turbines run a generator, which produces electricity and/or ancillary services for the grid

Renewables and storage go hand in hand:

Wind and solar facilities provide power with no emissions and no fuel costs. However, unlike traditional power generation resources, renewable power production is dependent on weather, which can be out of sync with customer demand. If renewable energy supply exceeds the demand for renewables it must be stored for later use or forever lost (curtailed). Demand for renewables is equal to total demand less electricity produced by i) generating units that lack the flexibility to turn off and restart in a short amount of time (e.g., nuclear plants) but are needed during peak hours, and ii) flexible assets that must stay online to provide grid reliability services. As shown in the example below, the Bethel Energy Center will act in two ways to alleviate curtailment of renewable production: i) Bethel will provide greater amounts of reliability services with less associated energy production than conventional generators and ii) Bethel’s compressor will add demand to the grid while charging. With less risk of curtailment, investment in renewable generation should continue to grow.

 CAES supports the efficient integration of renewable resources:

• In some regions, wind generates a disproportionate amount of its power during the middle of the night, when demand is lowest. The diurnal nature of renewables can create imbalances between supply and demand and put strains on the grid during periods of transition between low and high demand hours.
• CAES can utilize excess electricity created during the night to charge its storage cavern, then redeploy that energy to the grid during periods of high demand; this time shifting of energy can help to smooth steep transitions from renewable to non-renewable electrical generation. By improving grid accommodation of renewables, CAES promotes a cleaner, more economically efficient grid.
• By providing demand for renewable energy during offpeak hours, CAES reduces the potential for renewable energy curtailment and promotes growth in renewable production.