Biogas Genset: Working, Design, Benefits and Buyer’s Guide for Waste-to-Energy Projects

Energy planners, CSR teams and sustainability officers are all asking the same question: how can we reduce diesel consumption without compromising reliability? For sites that already generate or can generate biogas, a biogas genset offers a powerful answer.

Biogas gensets convert biogas produced from organic waste into electricity and sometimes useful heat. Instead of flaring gas or using it only for cooking, a well-designed biogas power system can supply captive power for pumps, blowers, lighting, motors and even export electricity to the grid where policies allow.

For project developers, this turns waste streams into a long-term asset, improves environmental performance and protects against volatile diesel prices. For institutions and industries, it is also a visible, reportable sustainability measure that supports climate and ESG commitments.

A biogas genset is a generator system specifically adapted to run on biogas instead of diesel or conventional natural gas. At its core, it consists of:

• An internal combustion engine designed or modified for biogas fuel.
• An alternator that converts mechanical energy into electrical power.
• A control panel, protection system and synchronization equipment, where needed.
• A complete gas train including gas blower, pressure regulation and safety devices.

Unlike diesel gensets, which rely on liquid fossil fuels, biogas gensets use methane-rich biogas produced in digesters from organic waste such as:

• Cattle and poultry manure.
• Food and kitchen waste from hotels and institutions.
• Organic sludge from sewage treatment plants (STPs).
• Agro-industrial residues and process waste.

A typical biogas power plant with a genset follows a clear sequence of steps, from waste handling to usable power output.

1. Feedstock Collection: Organic waste such as dung, food waste or sludge is collected and, if required, homogenized and diluted.
2. Anaerobic Digestion: The feedstock is fed into an anaerobic digester, where bacteria break down organic matter in the absence of oxygen, producing biogas (primarily methane and carbon dioxide).
3. Gas Storage: Biogas is stored in a gas holder or flexible gas storage system to balance production and consumption.
4. Gas Cleaning and Conditioning: Raw biogas is passed through scrubbers and filters to reduce moisture, hydrogen sulfide (H₂S) and particulates, improving engine life and performance.
5. Biogas Genset Operation: Cleaned biogas is fed to the engine through a gas train with pressure regulation. The genset generates electricity at the required voltage and frequency.
6. Power Utilisation: Electricity is used for captive loads, such as pumps, blowers, lighting, motors, or in some cases exported to the grid as per local regulations.
7. Heat Recovery (Optional): Engine jacket water and exhaust gas can be used to preheat feedstock, generate hot water or support process heating, improving overall efficiency.

When designed systematically, this waste-to-energy loop converts a disposal challenge into a long-term source of reliable, decentralized power.

As a biomass and biogas technology company, Enersol Biopower pays special attention to how these components work together, rather than focusing only on the engine or alternator in isolation.

Biogas gensets are most successful where there is reliable, long-term availability of organic waste and a clear, continuous power demand.

Correct sizing is critical for both technical performance and financial returns. Undersized units may waste available gas; oversized ones may frequently run at low load, lowering efficiency and increasing maintenance.

1. Assess Biogas Potential: Estimate biogas production based on feedstock type, quantity, retention time and digester technology.
2. Consider Gas Quality: Methane content and H₂S levels influence engine rating and derating factors.
3. Define Load Profile: Identify base, variable and peak loads to match genset capacity with realistic operating points.
4. Plan for Operating Hours: Decide whether the unit will run 24/7, during specific shifts or only to meet peak demands.
5. Integrate Redundancy: Decide if a second, smaller unit or diesel backup is needed for critical loads or maintenance periods.

At Enersol Biopower, genset sizing is always done in conjunction with digester design, gas cleaning systems and the broader energy needs of the site, rather than as a stand-alone generator sale.

Raw biogas contains impurities that can affect engine life and performance if not managed properly. A sound gas cleaning strategy is therefore essential.

Key Biogas Parameters to Monitor

• Methane Content: Determines energy value and influences power output.
• Hydrogen Sulfide (H₂S): Corrosive to engine parts and exhaust components.
• Moisture: Can cause corrosion and reduce calorific value.
• Siloxanes and Particulates: Relevant in some waste streams; can form deposits.

Typical Gas Cleaning Measures

• Condensate traps and cooling for moisture reduction.
• Iron-based or biological scrubbers for H₂S removal.
• Activated carbon filters for polishing, where necessary.
• Regular monitoring and media replacement schedule.

Well-designed cleaning not only protects the genset, but also ensures stable output, lower downtime and predictable maintenance intervals over the life of the project.

A biogas genset is not a “fit and forget” system. Successful projects invest in structured operation and maintenance (O and M) right from the design phase.

Regular O and M Activities

• Daily checks on gas pressure, engine parameters and unusual noise or vibration.
• Scheduled oil changes, filter replacement and spark plug inspection.
• Periodic overhauls as per engine manufacturer guidelines.
• Routine inspection and media replacement in gas cleaning systems.

When these activities are planned and budgeted, the lifecycle cost per kWh of a biogas genset can be very competitive compared to diesel, especially where feedstock is consistently available.

As a technology partner, Enersol Biopower typically recommends a combination of operator training, remote monitoring (where feasible) and clearly defined service intervals to keep performance close to design targets.

While every site is different, many biogas genset installations report a similar pattern of outcomes after stabilisation:

• Substantial reduction in diesel consumption for captive power needs.
• Better utilisation of digesters that were earlier underused or only flaring gas.
• Noticeable drop in odour and visible emissions compared to open waste handling.
• Improved energy security for critical processes and operations.
• Enhanced ability to report carbon and sustainability benefits to funders and regulators.

These benefits are particularly strong in projects where the power from biogas directly replaces expensive diesel-based generation or where grid reliability is a known bottleneck.

In many sites, biogas is not the only renewable energy option. A well-designed project can combine biogas gensets with biomass gasifiers, biomass stoves and thermal systems to optimise both power and heat.

• Biogas Genset + Biomass Gasifier: Biogas is used for continuous base-load power, while gasifiers handle peak thermal or power needs using biomass.
• Biogas Genset + Biomass Stoves: Electricity from biogas powers utilities, while biomass stoves or gasifiers handle large cooking loads in institutions and canteens.
• Heat Recovery + Thermal Applications: Jacket water and exhaust heat from the genset can preheat feedstock, generate hot water or support other process heating, increasing overall system efficiency.

As a biomass gasifier, biomass stove and biogas technology manufacturer and exporter from India, Enersol Biopower is uniquely positioned to design such integrated energy systems rather than treating each component in isolation.

Before committing to any biogas genset supplier, it helps to ask some structured questions to ensure long-term performance and support.

1. Experience: How many biogas-based installations has the supplier delivered, and in which sectors?
2. Engine and Alternator Make: Which brands are used and what is the track record for spares and service?
3. Gas Quality Assumptions: What methane content and H₂S levels are assumed in performance guarantees?
4. Integration Scope: Will the supplier also support digester, gas cleaning and balance-of-plant integration, or only the genset?
5. O and M Support: What training, manuals, AMC options and remote support are available?
6. Performance Guarantees: What electrical output, efficiency and availability numbers are committed, and under what conditions?

A transparent discussion around these points helps align expectations and ensures that both the technical and financial performance of the biogas genset project remains strong over its full life.

Biogas gensets sit at a powerful intersection of waste management, renewable energy and cost-effective captive power. When combined with well-designed digesters, robust gas cleaning and thoughtful O and M, they can reliably replace a significant portion of diesel-based generation for suitable sites.

For farms, STPs, food industries, institutions and municipal projects, a biogas genset is more than just a generator. It is a visible, measurable demonstration that waste can be turned into a long-term energy asset, supporting both financial sustainability and environmental responsibility.

As a biogas genset, biomass gasifier and biomass stove manufacturer, supplier and exporter from India, Enersol Biopower works with partners to design integrated systems that match local feedstock, power needs and project goals, rather than offering one-size-fits-all solutions.