Clean Energy

Biomass Renewable Energy

Biomass renewable energy is derived from energy sources such as garbage, waste wood, agricultural waste, landfill gas and alcohol fuels. At the Wadham Energy plant, rice hulls are fired in a boiler to generate heat that produces steam that turns a steam turbine that in turn spins an electrical generator which produces electricity for the northern California electrical grid.

Before Wadham began operations, disposing of rice hulls, which are removed from rice before it is sold, had become an increasingly troublesome problem for California rice mills. Over 360,000 tons of chaff, or hulls, are produced each year, far more than could be used in other beneficial applications. The unused balance had to be disposed. The slow-to-break-down rice hulls produce methane, a greenhouse gas (GHG), and open-field burning produces unacceptable levels of pollution. Wadham helps reduce greenhouse gases by transforming the hulls into fuel and generating enough electricity to power approximately 22,000 area homes without polluting the soil or air. This electric process is GHG negative in that the fuel was created by plant life absorbing CO2 and its combustion releases the same amount, however, if left to decompose, the rice hulls would produce methane, a gas that is 25 times more harmful than CO2 as a GHG.

Biomass helps California meet mandated GHG reductions. Diverting wastes from high-emission conventional disposal like landfill disposal and agricultural field burning reduces GHG emissions.

Wadham Energy is a member of the California Biomass Energy Alliance (CBEA). CBEA is comprised of the California’s solid fuel biomass power industry which is home to half the nation’s biomass power.

Landfill Gas Processing

All landfill operators recognize the opportunity for energy recovery from landfill gas (LFG). However, in the current energy market, there are attractive alternatives to on-site electric generation. Today’s technologies allow for methane recovery and the economic production of high Btu gas and/or vehicle quality liquefied natural gas (LNG). High Btu gas can be prepared to meet the most stringent of natural gas fuel specifications and delivered into local natural gas pipelines for sale to end users, including high efficiency combined cycle electric power plants. High quality vehicle grade LNG can be produced and used to fuel solid waste truck fleets, other vehicles, or sold into the bulk LNG market. Such fuel production strategies deliver to the landfill operator valuable revenues as well as recognition of environmental stewardship.

Enpower Corp. (Enpower) is seeking opportunities to develop projects for processing LFG to pipeline-grade natural gas. Enpower is prepared to provide a complete solution to recover valuable methane gas for delivery into a nearby natural gas pipeline or for the production of LNG, creating benefits for the landfill owner and the surrounding community. Enpower will work with you to determine if your landfill is a candidate for a LFG to high BTU gas facility. We provide complete services, including design, finance, build, own, and/or operate.


The landfill owner can expect to benefit from the project in several ways. These include:

  • Generating additional revenue.
  • Minimizing/controlling landfill odors.
  • Creating “green” energy.
  • Complying with environmental regulations.
  • Enhancing community image.


Though historically not as widely implemented as on-site electric generation projects, due to the market forecast of high natural gas pricing, Enpower finds that a high BTU gas project can often offer greater value than a LFG-to-electricity project. In areas where there is a low spark spread, which is the difference between the cost of fuel required to produce electricity and the price of that same unit of electricity, a high BTU gas project may be economically viable where a power plant would not. In addition to taking advantage of the high gas pricing, Enpower believes that a high BTU gas project offers many distinct advantages over an on-site electric generation project. These include:

  • Shorter development time, allowing for earlier payment of royalties. Enpower can build a gas process within 12 months of a notice to proceed compared to over 2 years for a power project.
  • Delivering the gas into a nearby pipeline for distribution so that electric generation can be maximized off-site, utilizing a high efficiency combined cycle power plant.
  • Lower noise levels and emissions than an electric generation plant, thereby creating greater community support.
  • Less permit requirements due to negligible air emissions.
  • Modular units can be easily moved and assembled. Allows for ease in future expansion as LFG flows increase.


LFG has been successfully processed at various facilities in the US for over 10 years. At one time, only very large sites were commercially feasible for processing LFG into pipeline quality gas. Processing LFG at smaller volumes is now possible given the current gas economics and improvements in processing technology.

The gas processing plant is comprised of several industry proven components that will produce a saleable gas stream. If hydrogen sulfide (H2S) levels are high, the LFG is first treated to remove these and other sulfur compounds.

Next, the gas enters the core of the gas plant. Enpower often prefers Air Liquide’s MEDAL™ system as the main component for the separation of methane from the LFG. As part of the core Air Liquide MEDAL™ system, a Pressure Swing Adsorption (PSA) pre-treatment system utilizing adsorption beds for CO2, siloxanes, and volatile organic compounds (VOC) removal is provided. The MEDAL™ system also includes activated carbon beds, designed to remove additional VOCs from the gas stream. The MEDAL™ molecular membranes remove the bulk of the remaining CO2. After treatment through the high Btu system, the product gas will contain virtually no contaminants and is dehydrated far below any pipeline specification.

An example of an Air Liquide MEDAL™ membrane system used in a larger gas processing application is pictured below.

If the oxygen specification for the gas pipeline requires the gas be treated further, Enpower will design the process to include a catalytic oxygen reduction system for additional removal of oxygen. The process also includes a nitrogen removal system to ensure that the gas meets a natural gas pipeline’s minimum heating value and does not exceed the maximum non-hydrocarbon inerts specifications.

Because our product gas is very pure, Enpower can also provide liquefaction or compression of the product gas to produce LNG or CNG for storage and/or transportation.

An example of an LNG storage & process facility.