Decarbonisation Technology August 2025 Issue

where hydrogen reacts with the captured CO₂ under controlled temperature and pressure conditions to synthesise methane (CH₄) and water. This exothermic reaction is highly efficient, and waste heat recovery within the system improves overall energy utilisation, pushing total power-to-methane conversion efficiency to roughly 57% based on the lower heating value (LHV) of the produced RNG. Quantitatively, a Carbon Bridge unit designed for a 1.3 MW input can produce

Figure 3 Commercial Carbon Bridge installation

Figure 3 ), with a flagship pilot project at the City College of New York (CCNY) spearheading the effort. This project utilises combustion exhaust CO₂ from multiple sources, integrating a closed- loop system that captures CO₂ from existing boilers and converts it into RNG through on-site electrolysis and methanation. The system uses off-peak electricity for efficiency. Standard Carbon and CCNY are planning a larger-scale Carbon Bridge deployment for the campus steam plant, offering a model for institutional decarbonisation and compliance with LL97. The company is also implementing Carbon Bridge systems at two secondary schools in NYC: one operates on the district steam supply, and the other relies on oil-fired boilers. These projects exemplify the system’s flexibility across different fuel sources and infrastructures. Health, environmental, and safety (HSE) considerations follow the NYC Construction Code with respect to flammable gases. The Carbon Bridge is designed to operate at atmospheric pressure to simplify the regulatory process and grant the technology the same permitting status as a standard commercial boiler. In parallel, Standard Carbon supplies off-site RNG under the StandardRNG brand to a range of commercial and industrial customers. Morrison’s Bakery in Queens, a notable industrial bakery with nationwide distribution, is adopting this off-site RNG to substantially

around 54 MMBtu of pipeline-quality RNG daily while capturing roughly 3.2 tonnes of CO₂. This output effectively replaces an equivalent volume of fossil-derived natural gas, directly eliminating the combustion-related emissions that LL97 targets. The produced RNG meets stringent ISO 13686 standards and regional utility requirements for heating value, methane content, and gas purity, allowing for direct injection into local gas pipelines or on-site combustion without modification to existing boilers. The first Carbon Bridge was installed on a 150 kW Tedom combined heat and power (CHP) unit, which powers an electric vehicle charging station and has operated continuously for nearly two years. It captures the CHP unit’s exhaust CO₂ and converts it on-site into renewable methane using grid-supplied, off- peak renewable electricity. The generated RNG is then re-combusted to power the EV chargers, creating a closed carbon loop that transforms intermittent renewable power into stable, high-value electricity. This system achieves significant cost savings by leveraging low- cost electricity. It delivers an electricity output valued at roughly five times the input electricity cost, demonstrating clear economic viability alongside environmental benefits. Real-world deployments P2G is moving from concept to demonstration through a series of deployments in NYC (see