Business Articles



How to ‘harvest’ electricity 



In 2011 against a challenging economic backdrop, Robert Gallagher owner of Willsborough Ltd in Campsie on the outskirts of Derry switched from selling crops grown on his arable farm, to growing crops to feed an Anaerobic Digester (AD).  Now with a fully operational biogas plant which generates up to 500kW per hour, Robert explains why he decided to harvest electricity as well as crops. 



“Up until 2011, the farm which has been in our family for generations, traded primarily in combinable crops such as wheat and barley. Cereal prices however were continuing to perform poorly so we decided to research how best to maximise the 480 acres of arable land on the farm.


We realised that a move into the renewables sector – in particular anaerobic digestion which could be fuelled by crops grown on the farm - might be a sustainable way to maintain and grow the business. At this time, the UK had very few AD plants so we travelled to Germany and Denmark where the biogas market is mature to understand the process and best practice.


While we applied for planning permission in April 2011, the plant only became fully operational in December 2015. During this period, much of our time was spent researching, navigating the planning process, securing finance, organising construction and getting connected to the grid.  With help from First Trust Bank, we made a significant investment in the technology required to run the biogas plant including a 500kW AD digester, feed clamps and a 500kW generator.   


All the crops we grow, predominately grass silage with some cereal crops, feed into the AD digester.  The digester breaks down the fodder which then produces biogas; mainly a mixture of methane and CO2. The biogas then powers our generator with the resulting electricity produced feeding into the national grid.  It’s a closed loop system meaning that nothing is wasted.  Any effluent created by the AD digester is used as manure to help our crops grow and mature – this also helps keep down fertiliser costs. Northern Ireland’s green energy targets are fairly ambitious with the region aiming for 40% of its electricity to come from alternative energy sources by 2020. AD technology is a great way to generate electricity from a green source as it is reliable and predictable - it doesn’t rely on the wind blowing or the sun shining - as long as the digester is operational, it will produce up to 500kW. In a year, our farm alone can produce enough electricity to power over 400 local homes.


It is however a challenging time for many in the renewable sector. Ireland operates in a single energy market which is set to be reformed and we are also at the mercy of exchange rates that will continue to fluctuate as the UK negotiates its exit from the EU.  We also face the prospect of business rates being imposed following the recent Land & Property Services (LPS) rate reform.  Aside from the capital cost of installing the biogas plant, feed stock is our single biggest expenditure. Over the years however we have learnt to keep this under control by growing grass silage. This crop is well suited to the climate in the North West and is one of the most inexpensive crops to grow and maintain.


Despite these factors and the changing wholesale cost of electricity, we are well placed as a business. Northern Ireland will always need safe and secure energy and as such we will continue to operate. For anyone considering a move into the renewables sector, the best advice I can offer is don’t believe everything a sales person tells you, do your own research and don’t be afraid to ask the professionals for help when you need it. Independent renewable energy experts, Action Renewables, has been a great support - from advising us on how to establish and maintain our plant to navigating the commercial energy market.”