Synergies between energy efficiency (EE) and renewable energy systems (RES)

The twin pillars of a sustainable policy

Any serious vision of a sustainable energy economy requires major commitments to both efficiency and renewables. Up to now, most policies and programmes for energy efficiency (EE) and renewable energy (RES) have been deployed separately. Significant synergies between both pillars can be realized however by combining these two policy agendas.

Last May, the American Council for an Energy-Efficient Economy (ACEEE) released a report on this topic.

The report discusses the following five synergies:

• Timing synergies. EE can provide large savings in the short and medium term, but the remaining opportunities in the long term will be limited. Conversely, RES will supply limited amount energy on the short term, but its opportunities are expected to expand over time.
• Economic synergies. Combining EE with RES can reduce the overall cost of the electricity system compared to a renewables-only policy.
• Geographic synergies. States with fewer RES can exploit EE opportunities to compensate. This will also help build a broader political consensus around a clean energy policy.
• Power system synergies. EE and RES have different load shape impacts, depending upon the time of day and season, so a combination of both can be a benefit to overall system operations.
• Several other synergies exist. For example, there are major opportunities for combined heat and power (CHP). CHP can play a role in both energy efficiency and distributed generation programmes.

The ACEEE report demonstrates these synergies with seven U.S. case studies. I will discuss these in the following days and weeks.