To achieve the goal of transitioning to 100% renewables by 2030, Barbados needs to add significant energy storage to the grid quickly. But doing so will require decisive action by both regulators and the private sector.
Solar and wind powers are referred to as intermittent sources of energy: they only produce power when the sun is shining or the wind is blowing. However, the electricity grid needs to meet the demand of consumers at all times, including at night, on a cloudy day and when the air is still. In fact, at any given instant, the aggregate supply of electricity for all sources of generation must be perfectly balanced with the aggregate demand for electricity by all consumers. When supply and demand get out of balance, the electricity grid can become unstable. In severe cases, that instability can trigger outages.
In the past few years, BLPC has been able to manage the intermittency of renewable generation using its existing fossil fuel powered generators. When renewable generation lagged, BLPC would just fire up boilers and turbines to make up the difference. However, so much renewable generation has now been added to the grid that a new problem has arisen. Sometimes the supply of power from renewable generators is temporarily greater than what the grid can absorb in the moment (for example on a sunny Sunday morning). This new problem cannot be solved with the equipment that is currently connected to the grid and can require wasting some of the clean energy by temporarily curtailing solar projects.
Storage is the key to balancing supply and demand. At times when renewable generation is greater than demand, storage facilities can soak up and store the extra energy. When demand is greater than renewable generation, storage facilities can inject that stored energy back into the grid. Storage can react very quickly to fix imbalances that occur over seconds or minutes. It can also be used over larger time scales, for example to store surplus energy during the day when the sun is shining and deliver it to the grid when it is needed at night or on overcast days.
There are many different types of storage facility. Undoubtedly the most familiar is battery storage, which is being deployed rapidly in many places around the world that have added lots of renewable generation. Pumped storage, which consumes power to pump water uphill and then generates power by letting that water flow down through turbines, is another proven technology. A smart mix of technologies will be needed to meet all of Barbados’ storage needs.