Creating clean green energy from food waste

MyGug has created an anaerobic digester that turns food waste into renewable energy and fertiliser

While most people would willingly do their bit for the environment it’s not always easy to find meaningful ways of making a difference. Most food waste, for example, ends up in the brown bin, which is fine as far as it goes. However, courtesy of husband-and-wife team Kieran Coffey and Fiona Kelleher there is now another option. It’s called MyGug and it’s an anaerobic digester aimed at small food businesses, restaurants, home kitchens and schools, that turns food waste into renewable energy and fertiliser.

MyGug was launched in February following four years’ development and an investment of €250,000, which was largely funded by the founders with support from Local Enterprise Office Cork North and West. The egg-shaped digester, which was designed by Coffey, who is a mechanical and environmental engineer, comes in various sizes and can be used to dispose of 99.9 per cent of food waste excluding bones and hard stones.

There are other waste digestion systems out there, but they are generally meant for large applications in agriculture or industry. MyGug makes the technology accessible on a much smaller scale and Kelleher says overseas interest in the product has been brisk, with units already shipped to the UK, Portugal and Berlin, where it is operational on an urban farm. The system is in use in a number of schools in Cork and is also attracting attention from sustainability-minded families who typically grow their own food and want an independent energy source as part of their lifestyle.

Dried bacteria are used to start the breakdown process and once the waste is macerated it flows into a storage tank. The end products are biogas and liquid plant feed. This can be used to enrich soil, while a small pump pressurises the gas for use for heating or cooking. MyGug is an enclosed unit, so there is no smell and no temptation for rodents, and the system can be controlled remotely by an app.


One and a half kilos of food waste produces roughly 1.5 litres of bio fertiliser and one to two hours of cooking time on a biogas cooking unit, which is included as part of the cost. The systems are professionally fitted by the company and it takes roughly two hours to set up a Micro MyGug, which is the smallest unit and costs €3,599. There are also midi and maxi units with larger capacities for commercial use, while the Mini MyGug (€8,900) is suitable for schools, where it fulfils the dual purpose of offsetting waste and energy costs while educating children about sustainability and how technology can make its contribution.

“Food waste emits methane gas when sent to landfill and this is much more damaging to the environment than carbon. The primary goal of MyGug is to cut the methane emissions associated with food waste,” Fiona Kelleher says. “MyGug has real added value for food businesses, especially where a cafe or restaurant is growing its own produce, as it gives them both energy and liquid feed on tap and they get payback very quickly.”

MyGug works in all weathers and climates from -20 degrees celsius to +40 degrees, which gives the system the edge in its niche as products from international competitors need a constant temperature to function. The manufacturing associated with MyGug has been outsourced to two companies in Meath, while the final assembly and testing is done in Clonakilty, Co Cork, where the company has three staff.

MyGug was recently chosen as one of 12 companies to participate in the second running of UCD’s AgTech accelerator programme for early-stage agtech and agri-food start-ups with global potential. This gave Kelleher, an accomplished musician and composer by background, an intensive dip into the new set of skills she’d need as a “green” entrepreneur including leadership, business development and making the business investor ready.