Project Types

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Wastewater biogas-to-energy

Wastewater is liquid from homes, businesses or agriculture which contains residual solids and a wide range of potential contaminants.

Wastewater treatment involves anaerobic digestion where bacteria digest the solids, creating significant amounts of biogas. This gas – primarily consisting of methane and carbon dioxide – can be captured and used to run engine/generators to produce electricity, heat or a combination of both. Using biogas in this way reduces greenhouse gases in two ways: it prevents the release of methane which is 21 times more potent than CO2 and displaces energy that would otherwise have been derived from fossil fuel sources. Alongside greenhouse gas reductions, wastewater treatment systems can improve water conservation in factory processes and reduce the release of toxic compounds and odours.
Geothermal energy

Geothermal energy originates from the radioactive decay of minerals within the Earth’s core and from solar energy absorbed at the planet’s surface. This heat can be used for: direct heating applications (such as heating buildings), generating electricity, or a combination of the both (also known as co-generation).

Small scale, direct-use applications like domestic heating can use heat from shallow ground, however industrial scale electricity generation requires much higher temperatures to be efficient. To access
these higher temperatures, geothermal power plants are often located near tectonic plate boundaries where the Earth’s heat can be harnessed more easily by using underground reservoirs relatively close to the surface. The power plants then route hot fluid (steam or hot water) from the geothermal reservoir through a turbine/generator – either directly or through a heat exchanger - to produce electricity. Geothermal is considered renewable because the heat in the Earth’s core is so abundant that minute amounts removed for energy production do not deplete this resource.
Biomass fuel switch

Biomass is all living matter including plants, crops, trees and waste products from milling and agricultural processes. Biomass can substitute fossil fuels – either in part or in full - to generate electricity, heat or both (known as co-generation).

Sustainably harvested timber is considered a renewable source of biomass because the trees that are removed are replaced, resulting in no net loss in stored carbon dioxide (CO2). Waste material such as bagasse (sugar cane stalks) and rice husk are another source of renewable biomass as they are by-products of existing agricultural processes. Using waste biomass for fuel can improve energy sustainability, provide additional income to farmers and overcome disposal issues. Switching to renewable sources of biomass not only prevents the release of CO2 from fossil fuels, it avoids the ecological damage associated with mining, drilling and transportation of these fuels.
Coal mine methane

Coal mine methane (CMM) is released from coal and surrounding rock strata through mining practices. Methane is an explosive gas which is hazardous to miners so is usually extracted and released into the atmosphere. However, methane is also a potent greenhouse gas (GHG) so preventing its release into the atmosphere presents an important opportunity to lower global emissions

CMM is primarily released from:

• Drainage systems that use wells to extract methane before mining
• Ventilation systems that circulate fresh air to dilute in-mine concentrations to below explosive levels
• Closed/abandoned mines from where CMM escapes over many years through open shafts and cracks.

Installing wells which extract CMM for capture and combustion prevents it from being vented into the atmosphere. During combustion, methane is converted into carbon dioxide which significantly reduces its global warming potential. In some instances, this waste gas is also captured and utilised to produce power and heat. This displaces energy produced from fossil fuel power stations, further lowering GHG emissions.
Afforestation/ Reforestation

Afforestation and reforestation projects are the planting or seeding of non-forested land.

Deforestation is responsible for between 15 and 20% of global carbon emissions and afforestation and reforestation projects are essential to the reduction of carbon emissions around the world. The difference between them is the length of time the land has not been a forest; for afforestation it is for at least 50 years and for reforestation it is since 31 December 1989.

As forests grow the trees absorb or soak up CO2 from the atmosphere through photosynthesis and sequester or hold it within their growing biomass (trunk, branches, leaves and root systems). This sequestered carbon stock is reliant on the forest remaining intact. Although some CO2 is released as the forest breathes, a forest that is growing and sustainable absorbs more carbon than it releases and approximately 50% of dry matter within forest ecosystems is carbon.

Forest ecosystems are a living environment in a state of natural flux: as carbon is sequestered or sunk in forests, it is exposed to the risk of release through infrequent events such as forest fire or insect attacks. To address this risk of non-permanence, the Voluntary Carbon Standard requires that upon verification of carbon credits, a percentage is withheld in a central buffer from each project. These units are withheld from sale and used as an insurance against any adverse events which would unexpectedly reduce the forest’s carbon stock.
Biomass cogeneration

Biomass is biological matter mainly coming from dead trees, yard clippings, left-over crops, wood chips, sawdust from lumber mills and livestock manure. It is a renewable resource which can be burnt as fuel to produce energy.

Biomass cogeneration plants use renewable biomass to simultaneously produce both electric power and steam, using less fuel than traditional facilities to produce the same amount of energy.

In addition to the environmental benefit of using renewable fuels, biomass cogeneration plants are 50 to 70% more efficient than conventional fossil fuel power.
Waste heat recovery

Waste heat is the heat produced by machines, electrical equipment and industrial processes. Generally it is considered a useless by-product and discarded. Capturing waste heat from large industrial plants allows it to be extracted and recycled back into the system.

Waste heat recovery boilers are usually placed on top of the heat sources and are used to generate steam which powers turbine generators and produces electricity, thereby reducing the environmental impact of industrial processes through their reliance of fossil fuel.
Landfill gas

Methane is a potent greenhouse gas (GHG) which can be extracted from landfills through wells dug at intervals throughout the site. It is the piped for combustion and/or use for power generation.

Combustion of methane converts the gas to carbon dioxide which has a significantly lower global warming potential than methane. To create power, generators are installed, converting the gas into power and heat.A landfill is a site for the disposal of a variety of waste materials including household, commercial, industrial and non-hazardous solid waste. Landfills range from open dumps to carefully designed and managed sophisticated structures built into or on top of the ground.

In the absence of oxygen, bacteria in the landfill breaks down the waste to produce landfill gas, consisting of around 50% methane, 50% carbon dioxide and a minute amount of non-methane organic compounds.

The capture of methane from landfill gas not only reduces GHG emissions, but also prevents the release of toxic, volatile organic compounds and odours.
Wind power

Wind power is an abundant energy resource which can be used to generate clean electricity through wind turbines.

The wind flowing through the turbines spins large propeller-like rotor blades. The movement of the blades rotates a shaft which is connected to an electrical generator which converts the kinetic energy of the wind into electrical energy. The output of wind turbine depends on the turbine’s size and the speed of the wind through the blades. The power generated by utility-scale turbines ranges from 100 kilowatts to as much as five megawatts. Grouped together into wind farms, turbines provide bulk power to the electrical grid which is then sent through transmission and distribution lines to homes and businesses.
Agricultural methane biogas

Methane released from manure management systems can be captured and used to produce clean energy through an anaerobic digester. These digesters are tight, oxygen-free containers which organic material such as animal manure and food scraps are fed into.

Naturally occurring bacteria in the organic waste breaks it down to produce methane gas, commonly known as biogas. Using generators, this gas is converted into electricity, delivering two environmental benefits. Firstly, reducing the volume of methane released into the atmosphere, and secondly, reducing the requirement for electricity from fossil fuel powered plants.

Livestock manure contributes approximately four percent of total human-induced methane emissions. Methane is a potent greenhouse gas, considered to be 25 times stronger than CO2 in terms of its impact on global warming.

Methane is produced and emitted during the decomposition of organic material in livestock manure. Three groups of animals – swine, dairy and non-dairy cattle – account for 80% of methane from livestock.