The Council determined a target amount of energy efficiency higher than the baseline conditions portfolio model results to reflect the values of adequacy, resilience, and flexibility. Energy efficiency provides these added values to the system, but none of these are currently fully reflected in the Regional Portfolio Model. As described as part of the recommendations for the RTF, the Council recommends the region work to better define and quantify these attributes of energy efficiency for enhanced modeling in the next power plan.
Adequacy
The time value of energy efficiency continues to play a vital role in the regional power system. Historically, energy efficiency provided a low-cost resource alternative to developing other generation, primarily thermal units. Today, ensuring an adequate power system depends upon meeting the load-resource balance. Solar energy through the region and across the WECC is providing excess supply during the daytime. As the sun goes down, other resources are required to meet the needs of the system. The Council’s analysis shows that the existing system, both hydro and thermal plants, have the capability to handle much of the flexibility to balance the change in solar. The analysis also shows that new resources that provide flexibility and interact with the hydro system provide additional balancing benefits. Additionally, the cost-effective reserves analysis demonstrates that energy efficiency, particularly those measures that save more during the morning and evening ramps and overnight hours, help to reduce the magnitude, frequency, and duration of adequacy events at a higher quality, but higher cost, than holding additional reserves. Efficiency can be used to mitigate the risk of not having the necessary level of reserves available.
To reflect this value, the cost-effectiveness methodology provides value to measures that save energy during the morning and evening ramp times. Due to the important role energy efficiency can provide in supporting system adequacy, the region should continue to invest in improving its understanding on the timing of energy use and savings of measures.
Resilience
Resilience can mean many things in the power system. For the purposes of the Council’s conservation program, resilience is focused on measures that support homes or buildings in their ability to ride-through extended power outages or extreme weather events. Recent events, like the historic wildfires across the west and the recent Texas freeze event, have resulted in long power outages. There are some energy efficiency measures that can provide significant benefit to building occupants during long-duration power outages. The primary example is weatherization. A well-insulated house will better maintain thermal comfort during long-periods compared to one with little or no insulation. In addition to added comfort, this can provide other benefits such as avoiding freezing pipes, avoiding temperatures that can create significant health impacts on occupants, and improving air quality (through improved air sealing) during fire seasons.
To date, the Council has not developed a method for quantifying the value of this resilience for inclusion in its power plan modeling. Additional work is needed to determine the valuation of this metric for energy efficiency, along with consideration of how this might apply to other resources.
Flexibility
As described above, the power system sees some value in resources that provide flexibility and can be integrated with the hydro system to balance needs. While energy efficiency itself is not a flexible resource, there are many measures that support load management for grid flexibility. This is achieved in two ways. One, there are measures that include enabling technology for supporting flexibility, such as built in smart controls. These controls allow for utilities or consumers to regulate their energy to shift towards other hours in the day in response to prices or system needs. The second group of measures are those that reduce or eliminate the impacts on end-use consumers from load management or demand response events. The primary example of this is weatherization. As described above, a well-insulated home helps to maintain thermal comfort, which allows for small adjustments to the heating or cooling setpoints of a household without resulting in occupant discomfort.
Since the costs and benefits of energy efficiency have traditionally been estimated in a silo, the Council has not embedded into its analysis these additional flexibility benefits. Additional work is needed to determine this valuation for energy efficiency. The region should also explore ways for improving the savings, costs, and benefit valuation of energy efficiency and demand response more holistically for improved modeling in future power plans.