The early February breakthrough in California energy storage rules under Net Energy Metering will still take time to be codified, but the great news is that energy from storage can be sold to utilities as long as the storage equipment meets a new Underwriters Laboratory standard. Under Time of Use rates, households with certified storage capacity can store energy during the day and sell it back to the utility during peak periods in the evening.
Equipment manufacturers are scrambling to meet the new UL Power Control Systems Certification Requirements. “The 2020 National Electrical Code Section 705.13 (Power Control Systems), is nearing finalization; it is anticipated the national standard will be published in January of 2019 as an addendum to UL 1741.22,” reads the CPUC decision on rulemaking, issued on Feb. 5th.
The California Public Utility Commission’s “DECISION GRANTING PETITION FOR MODIFICATION OF DECISION 14-05-033 REGARDING STORAGE DEVICES PAIRED WITH NET ENERGY METERING GENERATING FACILITIES,” came in large part as a result of intervention two years ago from the California Solar+Storage Association.
The gamut of equipment that must meet the new certification ranges from inverters to control systems to monitoring. The CPUC decision also finally would permit NEM paired storage systems larger than 10 kW, without a costly separate net generation output meter.
Among solar manufacturers that have supported the CALSSA petition is NEXTracker, whose NX Flow system was verified by UL as charging only from solar power. “NEXTracker is overjoyed to see this program come to fruition and we are so grateful for partners such as the California Solar and Storage Association (CALSSA), the California Public Utilities Commission (CPUC), and SepiSolar for spearheading on the policy front,” stated Alex Au, the company Chief Technical Officer.
“NEXTracker worked closely with PG&E, SCE, and SDG&E on the utility side to integrate meter and NEM policy requirements into software functions native to the equipment which would allow for cost reductions in labor and components, maximize NEM credit accruals, and to simplify the approval process,” Au said in a statement.
“As a unified front, we then took all requirements from key stakeholders and created tests and proposed standards with Nationally Recognized Test Laboratories (NRTLs ) such as UL. The result: greater efficiencies because of our mutual goals and alignment to integrate a future storage plus PV road map which will increase the rate of adoption and lower barriers for PV + storage behind the meter application,” Au said.
In January, CALSSA published a white paper, “Barriers to Maximizing the Value of Behind-the-Meter Distributed Energy Resources,” to help delineate many of the technical issues and terms of the final CPUC decision language.
“California policymakers have had great intentions to enable distributed resources to capture the additional value they can bring to the grid, but pushing past some of the technical challenges has been slow going,” said white paper author Scott Murtishaw.
The paper suggests that there is far more work that the CPUC must do to adequately update regulation of solar+storage. “Behind-the-meter DERs have the potential to provide a wide array of services to customers and the grid, but numerous barriers impede the provision of their full value. In this white paper we have described a framework for categorizing these barriers into five types. Many of the barriers are cross-cutting, implicating multiple policy areas at the CPUC as well as the CAISO,” wrote Murtishaw.
“As an alternative, the CPUC could open a new proceeding that would holistically consider each of these barriers (with the exception of the ADR exclusion on SGIP for which the CPUC has recently launched a stakeholder process) as well as interrelations among them. Consolidating these issues in one procedural venue may help the CPUC coordinate among the various policy areas touched on by these barriers, including SGIP, NEM, demand response, resource adequacy, IDER, and multiple-use applications for storage. To the extent this approach risks delaying further action on addressing incrementally in IDER, there will be a trade-off between holistic and piecemeal approaches,” the paper opined.
Storage design company SepiSolar also published a white paper in December, “California DC-Coupled Solar-Plus-Storage Net Metering Ruling: A Technology and Policy Review,” addressing the CPUC decision. This paper suggests that “When finalized, commercial DC-coupled solar-plus-storage installations will not only be able to benefit from NEM, but will also be able to increase solar system size, reduce installation and permitting costs, and quicken interconnection approval time.”