Tadhg Healy Nuffield Scholar 2008

Tadhg Healy is disappointed that the very real potential for anaerobic digestion on farms and in rural Ireland to generate renewable natural gas has been ignored by Ireland’s policy makers.

Tadhg Healy, a 2008 Scholar, researched the potential for anaerobic digestion on farms or within agricultural co-operatives. He is disappointed to see no progress in what could form a vital part of rural Ireland’s economic activity and energy generation decarbonating strategy.

My Nuffield study topic in 2008 was Anaerobic Digestion (AD) in rural Ireland. I had developed an interest in this for a few years previously and was very excited about the prospect to provide heat and electricity for my broiler sheds. But I could also see the bigger picture: AD could be developed all around rural Ireland to provide renewable energy to the grid and economic activity, and I often spoke of a plant at every co-op branch. Alas my bubble has been burst: fourteen years on I am sorry to report I do not have an AD plant on my farm and there are very few new AD plants developed around Ireland.

The topic brings up mixed feelings for me. AD as a technology is well proven and developed in Europe and the UK. There are approximately 200,000 plants in operation across Europe and approximately 700 in the UK, (of which over 100 are in Northern Ireland) most commissioned since 2013. There are about 20 plants in operation in Ireland, most of which were built before I began my Nuffield journey. This is extremely disappointing.

The necessary supports and policies in Ireland to promote AD development are poor or non-existent. This means potential developers have either delayed or shelved any project.

An SEAI study was commissioned to fulfil a government commitment to examine the economic potential of biogas and biomethane in Ireland. The results show that the equivalent of 28 per cent of Ireland’s 2015 gas demand could be supplied from renewable sources by 2050 and save up to two million tonnes of CO2 e per year.

In the context of the need to bring fossil fuel extraction to an end and reduce national carbon emissions while allowing farmers to diversify their income earning opportunities, this should be a no-brainer.

During my Nuffield research travels, I was particularly impressed by Dr. Colin Campbell. He has over 40 years’ experience in the oil industry, earned a Ph.D. in geology from the University of Oxford in 1957 and had worked as a petroleum geologist in the field, as a manager, and as a consultant. He has worked for Oxford University, Texaco, British Petroleum, Amoco, Shenandoah Oil, Norsk Hydro, and Fina, and has worked with the Bulgarian and Swedish governments. His writing credits include two books and more than 150 papers. He impressed clearly upon me the need for our society to understand that the age of abundant and cheap oil was very rapidly coming to an end, and to adapt accordingly.

The energy section of the global statistics website Worldometer.info today shows that just about 15% of global daily energy consumption in MWh is fulfilled by renewable sources. It also shows that we are around 15,000 days away from the end of oil availability, 57,000 days from the end of gas and 148,000 days from the end of coal.

Another salient point from my studies was that our current levels of usage is unsustainable, not least because the fossil fuel we use in one year took one thousand years to create in nature.

When we talk about AD, there is always a tension between food production and fuel production. Ireland is an efficient food producer, and we produce to very high standards. However, we import more than 90% of our energy requirements which leaves us very vulnerable in our ability to produce and process this food. Renewable energy production featured heavily in the programme for government, with targets of 70% renewable by 2030 for electricity generation, among other things.

I firmly believe the versatility of AD can play a big part in this, not alone as a means of producing energy but also to produce alternatives to chemical fertilisers. The digestate from AD energy generation is a valuable fertiliser. Furthermore, slurry from livestock can be processed through a digester, making the nitrogen in the resulting digestate 90% available to the plant when it is spread.

When it comes to carbon emission reductions and renewable energy generation, farmers are very much part of the solution to deal with both issues. It is high time we implemented a renewable energy generation strategy which gives its right place to anaerobic digestion on farms.

Read more about Tadhg’s Nuffield study topic and download his full report – click here