Green Generation uses an anaerobic digestion platform to transform organic/food waste collected from agri-food producers and retailers across Ireland into four separate products:
Product 1: Electricity (supplied into the national electricity grid)
Product 2: Biomethane (as a renewable fuel for vehicles)
Product 3: Organic fertiliser (supplied to local farmers)
Product 4: Mixed plastic flake (supplied to a sister company Paltech as raw materials for manufacturing a range of plastic products)
Green Generation take in 23,000 tonnes of organic/food waste per annum, primarily from Co. Kildare but also nationwide. Some key suppliers include Tesco, Birdseye, Boortmalt, Kildare Chilling, Glanbia, Domino's, Green Isle, Kildare Co Co (roadside/parks grass clippings), Food Cloud, Glenisk, Rudd's, Portumna Pastry, Irish Distillers. The food waste is depackaged by a team of 20 or so people.
We mix the food waste with some slurry from the neighbouring pig farm and feed it to three anaerobic digesters. These digesters produce biogas (a mixture of methane and CO2). Some of this biogas is used in a 1.2 MWe combined heat and power (CHP) plant to produce electricity which is used on site, with the excess supplied to the national grid (Product 1).
Most of the biogas generated from the digesters is purified to remove CO2. The resulting biomethane (97.5% purity) is suitable for injection into the national gas grid and used as a renewable transport fuel (Product 2). We own and operate the only renewable gas grid injection point in Ireland, and are the first (and only) biomethane supplier to the Irish National Gas Grid. We run our own HGVs on biomethane and won the SEAI 2020 Innovative Deployment of Renewable Energy Award for this endeavour.
The spent organic/food material from the digester process (referred to as "digestate") is pasteurised to EU standards and is currently distributed to local farmers as a nutrient-rich organic fertiliser (Product 3).
At the same time, the plastic packaging removed from food waste in the depackaging step is shredded, washed and dried to produce a mixed plastic flake (Product 4), for which we have achieved End-of-waste status. Working with a sister company, Paltech, we have developed innovative new technology that allows us to repurpose and transform this mixed waste plastic packaging into products such as flower pots and site traffic barriers, while diverting these plastics from landfill and incineration.
We are actively involved in several strands of R&D with a view to developing the Irish Bioeconomy.