Capstone Microturbines Deliver 2MW of Power With 75% Efficiency to San Diego Hospital

Capstone Energy+ has installed two C1000 Signature Series microturbines at Scripps Mercy Hospital in San Diego, delivering 2 megawatts of combined heat and power at an overall system efficiency of 75 percent. The project, delivered in partnership with BSD Builders, captures waste heat from electricity generation to supply the majority of the hospital's heating and domestic hot water needs. Once commissioning is complete, expected in October 2026, the system will also provide island-mode capability, allowing the facility to continue generating power during utility outages.

 

Why Combined Heat and Power Achieves Higher Efficiency

 

The 75 percent system efficiency figure is the technical centrepiece of this installation, and it stems directly from how combined heat and power systems work. A conventional setup draws electricity from the grid and generates heat separately, typically through gas boilers, meaning the waste heat produced during grid-scale electricity generation elsewhere is lost entirely rather than captured for local use. A CHP system instead generates electricity on-site and captures the heat that process produces as a byproduct, using it to meet the facility's own heating and hot water demand rather than discarding it, which is what allows the combined system to extract meaningfully more useful energy from the same fuel input than generating power and heat separately would achieve.

For a hospital specifically, that efficiency gain translates into lower energy costs alongside reduced fuel consumption per unit of useful energy delivered, since heating and hot water represent a substantial and continuous demand in a facility that operates around the clock and cannot tolerate interruptions to either power or heat.

 

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Why Island-Mode Resilience Matters for Hospitals

 

The island-mode capability, allowing the facility to keep generating its own power if disconnected from the utility grid during an outage, addresses a distinct risk category from efficiency: continuity of critical care during natural disasters or grid failures. Ryan Peña, project manager for corporate facilities at Scripps Health, described the value directly, noting that if utility service is disconnected due to a natural disaster or grid interruption, the facility continues producing its own two megawatts, keeping core operations running as an additional layer of protection and redundancy.

That resilience consideration has become increasingly central to how healthcare facilities plan infrastructure investment, since hospitals cannot simply pause operations during a power outage the way many other commercial facilities might, making on-site generation capable of operating independently from the grid a genuine patient-safety consideration rather than only a cost or efficiency measure.

 

What Isn't Specified: The Fuel Source

 

The release does not state what fuel powers these particular microturbines. Capstone's own company description characterises its systems as fuel-flexible, and notes that beyond power generation, its broader technology portfolio supports converting waste streams into usable fuel and capturing waste heat to produce thermal energy with a lower carbon footprint. Microturbines of this kind can typically run on natural gas or on alternative fuels including biogas or other waste-derived gas, but without the release specifying which fuel this Scripps Mercy installation uses, it isn't possible to characterise the project's actual emissions profile relative to grid electricity with any precision, only its efficiency advantage over conventional separate generation.

 

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A Pattern Across Mission-Critical Facilities

 

Capstone frames the installation as part of a broader trend of healthcare systems and other mission-critical industries investing in resilient, behind-the-meter energy systems as they seek greater reliability, improved efficiency, lower operating costs and long-term sustainability simultaneously. Chief executive Vince Canino framed resilience and sustainability as complementary rather than competing objectives for healthcare providers, arguing that both together strengthen operational performance and help ensure uninterrupted patient care.

Whether the completed system delivers its projected 75 percent efficiency consistently once commissioning finishes in October 2026, and whether the underlying fuel source used at this installation ultimately supports a genuinely lower-carbon energy profile rather than simply a more efficient use of conventional fuel, will determine how far this project advances the sustainability goals alongside the resilience benefits Capstone and Scripps Health have both emphasised.