Cogeneration, often called Combined Heat & Power (CHP), is the process of producing two or more forms of energy from a single fuel source—in our case, that source is clean, natural gas—right at your site.

A cogeneration system turns your building into a small, efficient power plant. At a large power plant, generating electricity from natural gas is only 30 percent efficient, due to heat loss.

But a cogeneration system captures otherwise wasted heat and puts it to work, gaining 50 percent efficiency, which combines with the existing 30 percent to make 80 percent efficiency. And you can measure the GHG/C02 emissions reductions you achieve every year, providing hard data to demonstrate your environmental responsibility.

Not every building can serve as a small power plant. Cogeneration systems are most effective in facilities that use electricity and hot water around the clock, such as apartments, condominiums, large swimming pools and 24/7 commercial-industrial facilities. Cogeneration is used extensively in Europe, with documented benefits.

North Coast Solar has been the Designer and Project Manager for cogeneration systems in prestigious buildings in the San Francisco Bay Area since 1986. Notable among these installations is Pacific Heights Towers in San Francisco. The system provides electricity to the common area, and creates hot water for domestic use plus provides hydronic space heating. If the PG&E power goes off, the cogeneration system at Pacific Heights Towers provides electricity for emergency systems, and doubling as an emergency generator.

Pacific Heights Tower Cogeneration project

Pacific Heights Towers
2200 Sacramento Street, San Francisco, California
60 KW Capstone Micro-Turbine

Park Bellevue Tower Cogeneration Project

Park Bellevue Tower
565 Bellevue Avenue, Oakland, California
65 KW Capstone Micro-Turbine

Case Study: 1200 California Corporation, San Francisco, CA

1200 California Corporation Cogeneration Project

1200 California Corporation
1200 California Street, San Francisco, California
60 KW Tecogen Cogeneration System (installed in 1994)
Upgraded to a 100 KW Tecogen Cogeneration System (installed in 2015)

Deck Monitoring - 1200 California Corporation

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Perhaps the most economically successful cogeneration system in the Bay Area is the project managed by North Coast Solar at 1200 California, a high rise condominium in San Francisco’s famous Nob Hill neighborhood across the street from Grace Cathedral.

The 60 KW Tecogen cogeneration system installed at 1200 California Street in 1994 generated electricity for the living units and common areas, and assisted the hot water system and hydronic space heating system. It produced $167,364 in net savings in 2012, and has generated $1,443,243 in savings 1994 – 2012.   Net savings are the value of the electricity and hot water generated minus the natural gas fuel and operating costs.

North Coast Solar was also the project manager for modernization of the cogeneration system when the building installed a new 100 KW Tecogen system in 2015. This system has a more advanced inverter technology and will produce more power as the building considers the installation of 8 electric car charging stations. The new 100 KW system received a $42,000 rebate from PG&E’s Self Generation Incentive Program (SGIP) for high efficiency technology.

North Coast Solar is proud to have been 1200 California’s energy consultant since 1990, helping them with their continuous campaign to become more energy efficient. North Coast Solar has provided energy consulting services to every building on the corner of California and Jones Streets in San Francisco including Cathedral Tower, Gramercy Tower, and Grace Cathedral.

The state of California provides incentives for cogeneration by allowing cogenerators to purchase natural gas at the same low wholesale prices paid by large power plants. Savings from cogeneration systems can range from $15,000 to $150,000 annually depending on a facility’s electric rate schedule and how much electricity and natural gas is being consumed. Businesses are eligible for a 10 percent investment tax credit when purchasing a cogeneration system. Cogeneration systems are also eligible for a PG& E Self Generation Incentive Program (SGIP).Depending on how much energy is produced, SGIP rebates can be tens of thousands of dollars. And the cogeneration system extends the life of the facility’s existing heating equipment, because the cogeneration system does most of the work.  

Unfortunately, with some cities such as San Francisco banning natural gas in new construction, natural gas cogeneration may become a high efficiency technology that is not permitted.  This is in-spite of the fact that heating hot water in existing high rise buildings may not feasible without natural gas.  Electric heat pumps are great in new construction but retrofitting them into existing multi-family buildings may not be feasible or economic.  Cogeneration should remain an option.

In our preliminary feasibility analysis, North Coast Solar can calculate the savings you can expect from a cogeneration system. Sometimes the feasibility analysis requires monitoring daily energy usage, which we can provide.