Community Solar
Utility Scale PV for Community Solar
GCarbon Coin is developing a combination of utility scale PV and long duration battery systems to provide reliable zero emission power for a community. The main technology innovation involves the coupling of PV panels to Form Energy iron air batteries, which provide 24 hours of storage at a low cost. This eliminates the need for a community solar system to draw on the grid for power to serve its subscribers. It also provides a highly reliable microgrid for supporting utility grid requirements in an emergency or high peak period.
This is important in the economics of community solar since it now means subscribers can get 100% of their energy from solar and batteries and no longer have to pay peak demand charges for electricity in the evening or monthly hook up fees. Instead, the community solar provider simply needs to negotiate a transmission and distribution fee for use of utility infrastructure, which can be a distribution fee only if the solar system is next to the loads, This also eliminates the wait time for interconnection to grids if the solar system can be placed next to the subscribers.
We are currently proposing to the Pacific Palisades community hit by the LA Wildfire a 36 MW solar PV and battery system. The project will provide zero emission electricity for 16,100 homes or housing units in West LA and Pacific Palisades. At least 51% of the recipients will be low & moderate income and the balance will be homeowners that lost their homes in the January, 2025 LA wildfires.
GCarbon Coin will work with the non-profit Solar Charge to Real Zero to get subscriptions from homeowners. The challenge for those rebuilding from the fires is that California Title 24 building codes require a solar system on the roof to meet electricity demand unless they subscribe to community solar. This adds $25-35,000 to building cost and has much less value on reducing utility bills given the elimination of net metering. The solar PV system proposed will consist of a 36 MW ground mounted PV array that will be built between the two communities in the subdivision and (assuming state public land is secured) that includes a 3 MW 300 MWh Form Energy iron air battery system. Additional PV capacity will also bee added near the Santa Ynez Reservoir. This will provide sufficient power for almost all of the residents in Pacific Palisades (excluding those that add solar to their homes) and an additional 8100 LMI households in West LA.
Solar PV and battery storage in utility scale systems is now the lowest levelized cost of electricity (5 c/kWh) over the 25 year life off the equipment (less than gas, coal & oil and 1/3rd the cost of nuclear). Pacific Palisades has solar resources of 2437.3 kWh per meter/year or 6.7 kWh/day. This means 120,000 sq. meters of utility scale solar area (12 ha. or 30 acres) is sufficient for 36 MW of power.
What makes the project particularly attractive is that half the capital cost can be recovered by a non-profit or the homeowners association from the US Treasury as a result of the Inflation Reduction Act. We estimate a total capital cost for batteries (3 MW 300 MWh) and 36 MW of solar will be around $96 million and if US materials are used and union labor then $48 million can be recovered as soon as the system comes on line. This allows the community solar system to offer a 20% reduction in rates to homeowners while offering zero emission electricity In fact, any embedded carbon emissions could be offset with tree planting and forest preservation so it is truly zero emission.
Water for Fires
Lakes, Ponds & Oceans for Fire Safety
The increasing wildfire problems around the world are largely the result of shifts in climate that are causing changes in vegetation, rainfall and severity of droughts. Housing is increasingly being built in urban/forest interfaces where consequences from wildfires can be devastating
The damages from wildfires in LA were made worst by the lack of both water and electricity. Electricity problems can be solved if there are two parallel systems in place, the regular utility supply and a community power system to back it up.
The bigger problem is sufficient water pressure at the hydrants. Pacific Palisades and Altamont fires both ran out of water in hydrants early in firefighting. One solution lies in rethinking recreation to make sure there is water near high risk subdivisions at the forest edge. While there was 171 million gallons of water not available because the St. Inez Reservoir was almost a year undergoing repairs, this would have run out of water quickly given the severity of the fire. What is needed instead is 3 additional reservoirs or ponds that are only for either recreation or firefighting. Use of park land surrounding the subdivision would be justified as visitors could then swim or boat on the facilities except in a wildfire emergency. This would add an additional 500 million gallons of water available for a major fire. While this has a cost, it also has high recreational value for millions of people living in LA visiting the firewater ponds.
The more important source of water is the Pacific Ocean. Pacific Palisades is right next to the ocean. Two pumping stations drawing water from beyond the surf zone could replenish 500 million gallons in the reservoirs very quickly and provide an infinite supply of water to fight any future fire. It will require investment in 4 pump stations and piping along the main roads heading up the hills. This could cover the whole area from the Malibu borderline to Santa Monica border including . Some new hydrants will be needed at the edge of the subdivisions that are set up for high pressure and potential use of salt water. Firefighters will also have to clean equipment if they ever have to use salt water. And certainly there will be some environmental damage from salt in the soil. But with proper flooding of the soil after its use, damage would be minimal.
The key in understanding why this is necessary and worth the investment is to consider the cost of business as usual. There is now severe land and water pollution from all of the chemicals from materials on houses burned in the fire that have seeped into land and water bodies. Estimated losses from the area is easily $75 billion and some estimates for LA area overall are much higher. Insurance rates for P&I (homeowners) insurance in California are expected to increase by 40% as a result of insurance company deals to keep them insuring high risk areas. This is an annual bill estimated at over $30 billion a year for homeowners.
There are many barriers to overcome to get this idea to be reality. They are not insurmountable. The City of San Francisco has built a parallel hydrant system that uses high pressure lines and larger hydrants and is hooked to San Francisco Bay if freshwater reservoirs run dry. The Santa Monica Mountain National Recreation Area or State Park Association would need to be convinced it is a good idea. But the firewater system could be set up with no reservoirs and just piping and saltwater pumps and hydrants and then ponds or lakes added later.
The other major party that will have to be convinced is LA Dept. of Water and Power. They are now in a lawsuit with Pacific Palisades homeowners over potential liability from their empty reservoir so they will likely lie low until this is resolved. But this might play in well with a settlement that pushed LADWP, State of CA the US Government to take proactive measures to protect from wildfires, rather than just rebuilding and hoping for the best when the next wildfire comes along.
Passive Fire Safe Housing
Super Efficient Fire Safe Housing
Sustainable housing design and resiliency requires thinking carefully about materials, design and construction to achieve the multiple goals of energy efficiency, fire safety and zero carbon emissions. Fortunately, there is a design standard that provides both super-efficiency standard and fire safe design; passive houses. Passive houses refers to a set of tight energy efficiency and building envelope sealing requirements that is then coupled with energy recovery ventilators, energy star appliance and electric heat pumps to greatly reduce heating, cooling and hot water demand. The measures result in a 50-90% reduction in energy demand versus new housing CEC Title 24 standards, which are the tightest in the country.
The advantage of proposing passive homes is that the CA Energy Commission is already on board with the standard and has it included as an option for complying with Title 24. The Passive House standard is a specific performance standard that must be met by the building envelope relating to insulation value, air infiltration, ventilation, heating & cooling equipment and appliances. The data on performance is reviewed by a certifying body which is primarily Phius in the US.
What is not in the standard but encouraged is fire safety. A Passive House is much safer in a wildfire than any other house because of its tight standards for air infiltration that keeps embers from entering the home. The only way air enters the home is through ducts that can easily be covered with fire safe screens. There are also closed eave requirements and triple pane windows that provide fire safety. What is missing is specific requirements for fire safe cladding and roofing If high fire rated cladding (at least A) is added along with roofing the resulting house envelope is much more fire safe and will likely survive a wildfire. In fact, 8 out of 9 Passive Houses designed by IR Architects in Pacific Palisades survived the fires with similar results from other Passive House architects.
The key to getting homeowners to meet a Passive House standard in WUI zones (Wilderness Urban Interfaces) is to require it in order to qualify for FAIR program insurance. This is the State of CA program to insure homeowners when no other insurance is available and is likely the only insurance people in Pacific Palisades or Altamont will be able to get. Linking rebuilding of homes to Passive House standards to qualify would immediately generate interest from architects and builders to meet the standard and would not require a change of codes.
The other element in rebuilding is the requirement for solar on new home construction. All of the homes that are completely burned will be considered new homes and subject to this requirement, This results in an expense of about $30,000 for an 11 kW system and higher if it is larger. There is a 30% or $9,000 Federal tax credit which may be useful or not since most homeowners will have large tax deductions they can take from home and belonging losses. The problem with this requirement is that the utility rate for electricity added to the grid used to be based on net metering (at 25 c/kWh) and is now based on avoided cost (which is now between 0-5 c/kWh). This means this solar system only cost will not be recovered in 7 years but will instead take 15-25 years or the entire system life. The economics are better if batteries are added but this doubles the capital cost. This is a core problem with rooftop solar due to the recent CPUC rate decision that will curtail solar in CA.
The alternative mechanism to comply with the Title 24 requirement is to subscribe to community solar. This has no capital cost since the investment is done by either a non-profit or a contracted 3rd party and homeowners only have to sign subscription agreements. The agreement will have to be for the building life and is subject to approval from the CA Energy Commission..
The advantage of community solar is when it is coupled with iron air batteries and provides 100% of the energy for the home. This then allows for subscribers to meet all of their energy needs at a 20% discount. It allows the community solar developer to earn a large portion of the payment for electricity as long as the fee charged by the utility is only a distribution fee (probably about 4 cents/kWh). This then allows for investment in batteries, since the cost of both batteries and solar is about 10 cents/kWh and after billing costs and distribution fee is deducted still provides about 5 cents/kWh gross margin.
This savings is important because if $30,000 in capital cost is avoided from community solar, building owners can then spend that same amount to cover any differential costs for Passive House certification (about 5%) and have a super-efficient fire safe home at the same cost as a minimum Title 24 standard home with rooftop solar..
This is important because at this point the combination of super-efficient construction and solar allows the home to be certified as “zero emission” . The CEC has a TECH Clean California program that offers loans and rebates to housing developers for going all electric and adding solar and then meeting tighter efficiency standards. This can help offset any cost differences for Passive House building standards and certification.
