The pressure on farmers to keep on changing continues unabated and nowhere was this more apparent than this year’s Energy and Farm Diversification Show at Gurteen Agricultural College, which showcased several alternative energy systems.

Touring the stands and talking to the exhibitors, it became apparent that managing the country’s energy resources and requirements is a field of endeavour that stretches far beyond the narrow box of electricity with everything.

Lack of commitment

There was also a sense that if Ireland really wants to kick the fossil fuel habit then there needs to be a clearer sense of purpose from the government.

In the agricultural sector there is increasing talk of farmers collecting methane from slurry and adding it to the products they already sell, after they have taken what they need to run the farm.

alternative energy show Gurteen
The Energy and Farm Diversification Show at Gurteen was well attended

As noble an idea as this is, the practicalities of doing so are not so straightforward, because the material from which the gas is to be extracted has to be collected first and then the methane captured.

Once captured it has to be separated from the carbon dioxide (CO2) and other gases with which it is mixed to make it pure enough for engines to run efficiently, none of this is simple or cheap.

Cost of anaerobic digestors

A small biogas digester being fed by slurry from livestock will cost around €900,000 and the prices head rapidly north from there according to Chris Long of agriKomp Ltd.

He would suggest that a herd size of 500 cows would be the minimum, and then there would need to be extra biomass required, probably in the form of silage to keep the unit running consistently throughout the year.

Slurry gas storage
New Holland, in conjunction with Bennamann, is effectively turning existing lagoons into AD plants with its methane collection system

New Holland is already actively pursuing an alternative path and has gone further than simply converting tractors to run on methane.

By taking a 50% stake in Bennamann of the UK, it has bought into a method of small-farm-scale capture and processing, obviating the need for expensive anaerobic digestion (AD) plants which can be demanding to run.

Big plans need big money

A near €1 million bill for an AD plant is an investment that is unlikely to happen without some serious grant aid from the government which, currently, is unforthcoming despite the talk of position papers, framework documents, establishing strategies and so on.

It is, as one exhibitor noted, simply kicking the can down the road again with no firm commitment to any particular course of action.

While it may be argued that farming receives quite enough support already, the demands being placed upon the industry cannot be met without a good deal of on-farm investment that would not otherwise be required.

Bord na Móna seeks biomass

Subsidies are, however, something of a problem for Bord na Móna, although not those provided by the Irish government.

The company finds itself looking for biomass to fuel a certain number of its power stations, which includes Edenderry, now that planning permission for operating the facility has been extended to 2030.

Edenderry power station
Edenderry power station has been granted planning permission for operation until 2030, burning biomass alongside the remaining cut peat

It is not the only generator doing so; Drax Global, in the UK, is another consumer of organic material and it has the support of UK government subsidies to go out looking for it.

Buying it up in Ireland, shipping it out to the other side of the British isles, would not appear to be the greenest business model, but it is the reality, leaving Bord an Móna short of its its target intake.

The practicalities of AD

If the price of an AD plant is one barrier to purchase then running may be another another.

Nick Torrens of DPS, which provides and installs the pumps and equipment associated with AD plants, explains that they need to be managed properly if they are to work effectively.

Consistency of input material type is the most important criterion with the preparation of it also being critical.

Short chopped, high dry matter (DM) silage is better than wet, un-chopped material, while sudden changes in the feedstock can dramatically affect efficiency.

Batteries alternative energy slurry pump
The progressing cavity pump is an essential element in any system dealing with semi-solid digestate

Stones and grit can also prove problematic and steps need to be taken to avoid their ingestion into the system for they can actually remain suspended in the digestate, leading to them passing out into the pumps.

Nick echoes the words of others in the slurry management business by advising that one over specifies the ancillary pumps and mixers and run them gently rather than try and push it all through at the maximum theoretical rate.

Keeping the diesel engine going

The overall message is that on-farm AD installations can be a huge investment in time, money and expertise, yet there are still ways for farmers to break away from their dependence on fossil fuels on a much smaller and more immediate scale.

One way of doing so is through the use of diesel replacements such as that supplied by Tria which has outlets in Co. Cork and now Mullingar, Co. Westmeath.

Thomas Flynn and Pat Murnane of Tria with a sample of the company’s HVO which remains useable down to -40°C

The product it supplies is Hydrogenated Vegetable Oil (HVO), a direct drop-in replacement for diesel fuel which does not require any modification to the engine or other additional measures.

Although made from otherwise waste products derived from the food chain, the product is not totally independent of fossil fuels for the chemical process used in producing HVO requires the input of hydrogen, most of which is derived from natural gas.

Alternative energy needs diversification

Anthony Miller, business development director for the company, notes that although all the indications are that there is enough raw product available to happily sustain further growth, it must not be seen as the only solution.

He suggests that HVO should be regarded as just one answer to becoming independent of fossil oil.

There are other ways forward which are being promoted by other companies, the placing of the energy management eggs in one basket, be it HVO, hydrogen or batteries, would be a grave mistake he contends.

This was a message that was being repeated elsewhere at the show as indicated by the sprinkling of companies promoting biomass use on a more local scale, in and amongst those selling solar panels and electrical systems.