Turning waste into the energy to power construction

Biogas, created by turning organic waste into renewable power, is emerging as a game changer for construction. It offers the opportunity to reduce emissions on site, cut waste disposal costs and is helping to deliver carbon zero projects. While biogas is often associated with agriculture and municipal waste management, it is now becoming increasingly relevant to construction as both a power source and as part of a wider resource-efficient economy, writes John Ridgeway.

Biogas is a type of renewable energy produced when organic materials such as food scraps, agricultural residues, wastewater sludge, or even construction site biomass are broken down in the absence of oxygen. This process, known as anaerobic digestion, produces a gas mixture primarily composed of methane and carbon dioxide. The methane can then be captured, purified and used for electricity generation, heating, or as a vehicle fuel.

For construction, the significance lies in its versatility. Biogas can power site generators, feed into district heating systems for housing projects and serve as a direct substitute for fossil natural gas in industrial processes such as cement production. With construction responsible for nearly 40% of global energy-related carbon emissions, the ability to replace fossil fuels with a renewable energy source derived from waste offers both environmental and commercial benefits.

A long road to today’s innovation

Biogas is not new. The concept of capturing methane from decaying organic matter dates back centuries, with small-scale use documented in 17th-century Europe and more systematic applications emerging in the 19th and 20th centuries. However, for much of this history, biogas remained a niche solution, limited by technological constraints and competing with the easy availability of coal, oil and natural gas.

It is only in the last two decades, under the combined forces of climate targets, waste management pressures and improved anaerobic digestion technologies, that biogas has gained mainstream momentum. Countries such as Germany, Sweden and Denmark have pioneered biogas integration, with plants feeding into national gas grids. In the UK, government incentives have supported the rollout of anaerobic digestion facilities tied to both agriculture and municipal waste.

The move from a niche to a viable mainstream solution is critical for construction. It means that biogas is not just a laboratory curiosity or a pilot project, but a maturing industry with supply chains, infrastructure and commercial models that construction companies can begin to engage with today.

Sourcing Biogas

The feedstock for biogas production is almost everywhere. Local authorities collect household food waste, water utilities manage sewage sludge and agricultural operators deal with vast volumes of manure and crop residues. Increasingly, construction and demolition sites themselves are becoming part of this ecosystem, with biodegradable site waste and timber offcuts being diverted into anaerobic digestion facilities rather than landfill.

In practical terms, construction firms will rarely produce biogas directly. Instead, they will become consumers and partners in a circular system. Contractors can source biogas through energy suppliers who blend biomethane into national gas networks, through district heating schemes that rely on anaerobic digestion, or through direct purchase agreements with local facilities. In some cases, large construction clients with ongoing energy needs - such as hospital trusts, universities, or industrial estates - are exploring on-site or near-site digestion facilities as part of their energy strategies.

The fact that feedstock is so varied and widely available makes biogas uniquely scalable. Unlike hydrogen, which requires large new production infrastructure, or solar, which depends on land and weather, biogas grows out of waste streams that already exist and are often represent a disposal problem.

What does Biogas mean for the construction industry?

The implications for construction are both direct and indirect. Directly, biogas can provide renewable, lower-carbon energy to construction sites. Generators powered by biomethane can replace diesel units, reduce emissions and improve local air quality. For off-grid sites or temporary projects, this could become a game-changer.

Indirectly, biogas contributes to the wider decarbonisation of the built environment. Buildings and infrastructure increasingly depend on green heating and power sources to meet net zero commitments. As housing developments connect to district heating networks or as industrial facilities switch to renewable gas, construction will be at the centre of delivery. Developers, contractors, and designers who understand the role of biogas in energy systems will be better placed to future-proof projects, meet planning requirements and satisfy increasingly sustainability-conscious investors and occupiers.

There is also a reputational and procurement angle. Major clients, particularly in the public sector, are asking contractors to demonstrate sustainability in their operations. Adopting biogas-powered equipment or committing to renewable energy supplies that include biomethane can strengthen bids and position companies as leaders in low-carbon delivery.

Current availability and adoption

Biogas is already available today in many regions. In the UK, biomethane is injected into the national gas grid at dozens of sites, with suppliers offering “green gas” tariffs that blend biomethane with natural gas. In the United States, renewable natural gas projects have been expanding, particularly in states such as California that offer incentives. Across Europe, the biogas sector is more advanced, with some countries already sourcing over 10% of their gas demand from biomethane.

On construction sites, adoption is patchier, but growing. Pilot projects in Northern Europe have demonstrated the feasibility of using biogas-powered machinery and generators. In the UK, some housebuilders are already linking schemes to district heating systems powered by anaerobic digestion. The technology is therefore available and usable now, but wider use will depend on price competitiveness, supply chain integration and awareness among contractors and clients.

Long-term prospects

The long-term prospects for biogas look strong, but not without challenges. Analysts forecast that biomethane could supply between 10% and 20% of global gas demand by 2040, depending on policy support and investment. For construction, this translates into a steadily growing pool of renewable energy options that will influence both project delivery and building operation.

The sector is also evolving technologically. Upgrading processes are improving the efficiency and purity of biomethane, making it fully interchangeable with fossil gas. Advanced digestion techniques are expanding the range of feedstocks, while integration with carbon capture technologies is opening the possibility of carbon-negative energy.

However, scaling biogas is not automatic. Feedstock supply is dispersed, plants require upfront capital investment and there are competing demands for organic waste. The construction industry must therefore engage actively, not passively, if it is to benefit. By forming partnerships with energy suppliers, advocating for supportive policy and demonstrating demand for biogas-powered solutions, contractors can help accelerate availability and bring costs down.

The timeline for regular use depends on how we define “regular.” Today, biogas is already in use in heating networks, grid gas supplies and in some pilot projects, powering construction sites. Within five years, it is reasonable to expect that biogas will be a mainstream option for contractors seeking alternatives to diesel generators, particularly as regulations on air quality and emissions tighten.

Within a decade, as net zero deadlines loom and infrastructure investment expands, biogas is likely to be embedded in many large-scale construction projects, particularly those tied to public sector funding or long-term operational energy needs. By 2040, biogas could be as common a feature of the construction energy landscape as solar panels or heat pumps.

The speed of adoption will be shaped by policy, investment and client demand. But the trajectory is clear - biogas is moving from the margins to the mainstream and construction will be one of the sectors most affected.

Challenges to overcome

Despite its promise, biogas faces hurdles. Costs remain higher than fossil natural gas in many markets, although this is partly due to subsidies that favour fossil fuels. Infrastructure for collection, upgrading and distribution is uneven. And while the feedstock base is large, it is not infinite. Competition for organic waste between energy producers, composters and other industries will intensify as biogas scales up.

For construction, the challenge is to integrate biogas without assuming it is a silver bullet. It will be one part of a wider energy mix that includes electrification, hydrogen and efficiency measures. Contractors will need to stay informed, flexible and ready to use the right energy solution for each project.

Biogas represents a rare convergence of sustainability and practicality. It tackles two pressing problems at once - waste disposal and fossil fuel dependence. For the construction industry, it offers immediate opportunities to cut emissions on sites, long-term benefits in delivering low-carbon assets and strategic value in positioning firms for a net zero future.

The material is here, the infrastructure is growing and the prospects are strong. What remains is for the construction sector to recognise biogas not as an agricultural curiosity, but as a cornerstone of its future energy strategy. By doing so, it can help accelerate adoption, influence policy and ultimately build not only homes, offices, and infrastructure, but a more resilient and sustainable energy system for the generations that will live and work in them.