Assessing Demand Response Potential in Small Commercial Buildings
From eSociety, October 2019
Proper building demand management could improve grid operation and robustness, according to research from Science and Technology for the Built Environment. Researchers conducted a national assessment of building demand responsive control strategies that included seven types of commercial buildings, five climate locations and a variety of rate structures offered by the major utility companies.
Building owners, utility companies and system operators can use the study’s findings to identify the most effective and economical solutions to mitigate the adverse impact of renewables and to improve the grid operational efficiency, according to Jie Cai, Associate Member ASHRAE.
Cai and James Braun, Ph.D., Fellow ASHRAE, wrote “Assessments of Demand Response Potential in Small Commercial Buildings across the United States” about the study and its findings.
Cai furthers explains the significance of the research.
1. What is the significance of this research?
This research conducted a national assessment of building demand responsive control strategies across the U.S. The study covered seven types of commercial buildings, five climate locations and a variety of rate structures offered by the major utility companies across the U.S. The reported performance metrics include peak demand reductions, utility savings and indoor comfort impact.
2. Why is it important to explore this topic now?
The U.S. electric grid has seen dramatic increases in renewable generation in recent years and deeper renewable penetration causes significant challenges for reliable and stable operation of the grid, e.g., the “duck curve” observed in the California market due to high solar power utilization.
Buildings are responsible for 75% of national electricity use in the U.S. and can provide grid reliability and stability support in a cost-effective manner.
Results presented in this paper can be leveraged by building owners, utility companies and system operators to identify the most effective and economical solutions to mitigate the adverse impact of renewables and to improve the grid operational efficiency.
3. What lessons, facts and/or guidance can an engineer working in the field take away from this research?
Thermostat setpoint scheduling can provide the most significant peak demand reductions and utility cost savings. Savings potentials from lighting and shading controls are marginal. However, inappropriate thermostat settings could compromise indoor comfort and reduce the savings potential.
We found optimal temperature setpoints of 70°F (21°F) for pre-cooling periods and 75~76°F (23.9~24.4°C) for demand-limiting periods.
4. How can this research further the industry's knowledge on this topic?
The HVAC industry has adopted the demand response (DR) feature to some extent. High-end commercial products already have built-in demand responsive control options. This research identified the optimal temperature settings for the pre-cooling and demand-limiting periods, which can be adopted by the industry to further promote deployment of DR.
In addition, the national assessment results clearly identify the most economically viable regions/locations to deploy DR, and this can be used by HVAC manufacturers to adapt their marketing strategies.
5. Were there any surprises or unforeseen challenges for you when preparing this research?
We carried out a survey to collect the most updated electricity rate schedules across the U.S. and found significant variations across different regions of the U.S. Electricity can be as cheap as half-cent per kWh in Colorado and as expensive as 25 cents/kWh in California. This non-uniformity makes DR less favorable for certain regions compared to others.