California ISO releases energy efficiency and demand response roadmap

Recent technology trends indicate that there will be a greater reliance on demand response (DR) and enengy efficeincy (EE) as well as other forms of distributed energy resources (DER) such as microgrids, rooftop solar, electric vehicles as well as energy and thermal storage facilities in order to maintain a
reliable and affordable power supply while minimizing the environmental impacts of conventional electricity generation. 

Some of the immediate challenges Caliornia is facing are the shutting down of the San Onofre Nuclear Generating Station as well the potential loss of about 6 GW of coastal power plants because of new EPA rules for the use of sea water for cooling. 

Anther challenge is the addition of intermittent energy sources primarily wind and solar power to the grid. DR and EE are expected to play new roles in the future as flexible resources to balance fluctuations in the grid due to distributed intermittent energy sources.  California has committed to a goal of 33% renewable energy generation by 2020. Greater operational flexibility is required as more distributed intermittent renewable energy sources are added to the grid. Because the grid is increasingly comprised of many geographically distributed small energy sources, it is expected that geospatial technology will play an increasingly central role in managing the grid as it evolves from a small number of centralized power plants to a distributed generation system.

Germany is also addressing the challenge of balancing generation and demand with increasing intermittent energy sources distributed over larger areas.  The Deutsche Energie-Agentur GmbH (dena) - the German Energy Agency - commissioned a study led by Prof. Dr.-Ing. Christian Rehtanz, Technical University Dortmund/ef.Ruhr to determine the scope of grid system services in the context of an increasing supply of intermittent energy.  In particular, the study looks into the extent to which distribution grids can contribute to grid stability for the transmission grid, and the role renewable energy systems, storage facilities and demand-side management (DR and EE) need to play to ensure grid stability and resilience

The “duck curve” illustrate how the California power demand is likely to evolve as more energy is produced from renewables.  In the graphic “net load” is the the actual demand on the system minus generation from intermittent sources and is calculated by taking the forecasted total demand and subtracting the forecasted electricity production from wind and solar generation resources.

These curves represent the variability that the California Independent System Opertaor (CAISO) must balance with other resources including EE and DR. One way to enable reliable grid management is load reshaping, applying EE and DR resources as behavior modifying mechanisms to change the shape of the net load curve.  The load-modifying path aims to flatten the demand curve by attenuating the peaks and valleys and to avoid steep ramps in power generation.

The other approach is to manage procurement of resources in response to the grid needs.  The resource sufficiency path focusses on ensuring the needed flexible resources are available including dispatchable power capacity, storage and DR.

The CAISO is working with the California Public Utilities Commission (CPUC) and the California Energy Commission (CEC) to create a market for DR and EE based on smart grid technologies to transition the state toward a more reliable and environmentally-sustainable electric power system.  CAISO has just released a roadmap for EE and DR entitled “Demand Response and Energy Efficiency Roadmap: Maximizing Preferred Resources”.

The roadmap anticipates the size, timing, and geographic distribution of newer, more flexible energy generation resources and lays out the plan for lowering market barriers that inhibit DR/EE from competing alongside conventional resources.  The roadmap identifies four pathways which the CAISO sees as essential for enabling a viable online a DR and EE market over the next three years:

1. Load Reshaping Path - use incentives to modify consumption patterns to “flatten” demand and reduce the need for peaking generation capacity.
2. Resource Sufficiency Path - ensure enough generation or DR/EE resources are available at the right places and at the right times.
3. Operations Path - optimize use of resources (demand and supply). CAISO will have to change some existing policies as well as develope new market products to expand EE/DR market participation.
4. Monitoring Path  - monitor progress and outcomes