As solar, wind, and other renewable energy methods become more prevalent, micro- and offgrid installations will suffer from frequency instability and high risk of blackouts. Changes in wind and/or solar energy production have an impact on the frequency a grid can deliver. Also, if the exact amount of electricity being used is not matched by generation, the frequency is once again impacted. If demand is higher than supply, frequency will fall, whereas if there is more supply than demand, the frequency will rise.

The consequences can be severe. Deviations from the standard 50 Hz risk damage to infrastructure, machinery, and equipment.

Micro-offgrid-frequency-variation-without-ultracapacitors

Ultracapacitors can be used to deliver and absorb high power with an extremely fast response time, meaning they are ideal for frequency regulation applications in micro- and offgrids. Ultracapacitors provide a stable supply of energy, minimizing frequency deviations, as well as offering transient support for diesel generators, allowing them to operate closer to rated power for base load.

Micro-offgrid-frequency-variation-with-ultracapacitors

The benefits of ultracapacitors are numerous: maintaining continuity of energy supply, ensuring optimal integration of renewable energy sources, and voltage and frequency support to mitigate power quality events.

Use case: Independent Island Grid

Island-grid-ultracapacitors-micro-offgrid

Skeleton Technologies' SkelGrid ultracapacitor system is used to stability and protect the grid on an island grid. SkelGrid provides 90 kW power boost to keep the frequency stable, allowing the grid to operate independently of the national grid. The grid is powered by hydro, wind turbine, and PV installations, and ultracapacitors ensure a stable grid.