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The New California Solar Rooftop Mandate

What is the California Solar Rooftop Mandate

Beginning in 2020, most new homes built in California will be subject to the California Solar Rooftop Mandate — a program that incorporates advanced efficiency measures and rooftop solar. The California Energy Commission (CEC) voted unanimously to adopt the rooftop solar panel mandate as part of the state’s Building Energy Efficiency Standards. This decision came after more than two years of work with experts in the energy industry. The original Title 24 standards were updated and the projections aim to reduce home energy use by 53 percent. This is estimated to save Californians $1.7 billion in energy costs over the next 30 years. These numbers, which were studied by the CEC, don’t look at the energy demand or technological advances, which means that savings could be even greater over time.

Who will the California Solar Mandate Apply To

The Rooftop Solar Panel Mandate applies to all new residences and major home renovations on buildings that are under three stories high, starting on January 1, 2020. If a new home built after 2020 isn’t able to comply with the California solar panel mandate, then the home will need access to community solar or be able to offset energy use with different efficiency methods. Some homes may be exempt from the rooftop solar panel mandate if they don’t meet certain requirements. According to the CEC, it’s estimated that 15,000 new homes are built each year that include solar panels. When the new California Solar Mandate takes effect, that amount should rise to around 100,000 new solar homes per year.

How Will the Rooftop Solar Panel Mandate Be Funded

An important factor in creating the new rooftop solar panel mandate was to ensure that all Californians could afford the solar systems and energy upgrades. The cost to add solar to a new home is expected to be an additional $8,000 to $12,000. There is some opposition to the solar panel mandate. Some experts believe that building large-scale solar projects would be a much more sensible and cost effective way to make California’s energy system greener.

The Solar Energy Industry Association (SEIA) estimates the California Solar Rooftop Mandate will amount to an extra 200 megawatts of solar deployed in the state annually. This is a conservative estimate since some homes will be able to have small solar systems under 3 kilowatts. Last year California added 858 megawatts of residential solar from 127,000 new residential solar systems, with an average size of 7 kilowatts. Along with the rooftop solar panel mandate, the new building standards will offer a credit for combining solar with energy storage. Currently, the standards offer only credit for solar.  The new 2019 code will ensure that more homeowners benefit from efficiency while also getting an incentive from solar plus energy storage

Compliance with the Solar Panel Mandate

Homebuilders who will be responsible for compliance with the new codes will have an option in how they work with the new rooftop solar panel mandate. The development costs can be added into the mortgage, the system can be leased, or there are other ways to finance. The customer can decide which option suits them best. On average, it’s estimated that homeowners will save $40 a month on their electricity bills possibly more. What is even more important is that they will be contributing new standards for efficiency, and helping to make the grid more reliable.

California also has a mandate for new homes to be “net-zero energy” by 2020 which means they produce more energy than they use. The same applies to commercial buildings to be net zero by 2030. The California solar mandate helps the state to reach that goal. The rooftop solar systems required under Title 24 must be sized with annual electrical output equal to or greater than the home’s annual electrical usage.  This is determined by an equation specified in the code. It’s estimated that the average solar system size across California’s 16 climate regions would be 3.38 kilowatts. The smallest model system sized at 2.7 kilowatts in San Diego and the largest sized at 5.7 kilowatts in Palm Springs. Of course, these are projections and some of the numbers could vary in either direction.

While not everyone is in agreement that homebuilders should be forced to incorporate the California Solar Rooftop Mandate, everyone can agree that renewable energy is important for our future.