APPLICATIONS OF TECHNOLOGY:
- Monitoring and control of distribution grid
- Estimates real-time generation of behind the meter distributed PV
- Designed to become more accurate over time
As the penetration of distributed generation on the grid from resources such as wind and solar increases, so does the complexity of operating a power system in real-time. For continuing, instantaneous balance between generation and load, visibility of the instantaneous generation of intermittent resources is needed.
To this end, Berkeley Lab researchers led by Emma Stewart have developed a technology for estimating renewable energy generation from behind the meter, i.e., residential and small commercial locations on distribution feeders. The technology utilizes real world measurements obtained from a distribution grid substation and is two times more accurate than existing technologies.
The invention employs synchrophasor data and limited irradiance, or irradiance proxy, measurements. With machine learning and high-resolution data collected through a network of more sensitive micro-synchrophasors, the technology can become more accurate over time. Additional sensor measurements improve algorithm accuracy as well.
Present methods for estimating behind the meter renewable energy generation include basic methods of irradiance measurements and information on the installed capacity, installed which have an root mean square error (RMSE) of ~10% accuracy at best for all sky conditions, assuming site-specific irradiance measurements, compared to the Berkeley Lab technology’s RMSE of ~6% with limited measurement locations. Although there currently exists net-metering of PV sites, such as that used for the California Solar Initiative (CSI) rebate program, these measurements are usually low-frequency measurements of energy for determining payouts. The low granularity of these measurements, coupled with the difficulty of extracting residential PV generation, make them unsuitable for the purpose of real-time estimation of instantaneous generation.
DEVELOPMENT STAGE: Validated against utility-measured data
FOR MORE INFORMATION:
Kara, E., Roberts, C., Tabone, M., Alvarez, L., Callaway, D., Stewart, E. Towards real-time estimation of solar generation from micro-synchrophasor measurements. Cornell University Library, July 2016.
STATUS: Patent pending. Available for licensing or collaborative research.