Net metering allows buildings with on-site renewable energy systems (primarily solar) to send excess electricity to the grid and receive credits for that power, offset against grid consumption during non-generating periods. Net metering policies enable cost-effective renewable energy economics by valuing exported power at the retail electricity rate rather than the lower wholesale rate. Buildings with net metering can achieve positive annual energy balance and effectively reduce electricity costs to zero.
Policy Mechanisms
Net metering credits accumulate monthly or annually depending on utility policy, with unused credits rolling over or being paid at wholesale rates (typically $0.03-$0.05 per kilowatt-hour). Most net metering policies allow credits to be carried forward 12-24 months before expiration. Building-integrated solar systems can generate 3-6 kWh per square foot annually in optimal climates, providing net metering benefits for 10-15 kW rooftop systems on commercial buildings.
HVAC Integration
Net metering economics improve when paired with time-of-use rate structures and load-shifting HVAC strategies that maximize self-consumption during solar generation hours. Electric heat pumps and efficient HVAC systems increase electricity consumption (versus gas systems), allowing buildings to better utilize on-site solar generation. Net metering policies vary significantly by state and utility; some jurisdictions have eliminated or reduced net metering rates in recent years.