Ann Schmelzer, Cummins’ general manager for global agriculture, explores the sustainability benefits of natural gas and biomethane power for agriculture applications – and why we might see more farmers consider it as a future power option.Â
When compared to the diesel engine and a recent array of full-battery electric and hydrogen prototypes, you could argue that natural gas power hasn’t had the same attention in the agriculture sector.
Natural gas is most often seen in on-highway bus and truck applications and this is an area where Cummins has been successful, counting Volvo and Solaris amongst its European customers. But does the business case stack up for natural gas in agricultural settings?
When we think of natural gas in agriculture, power generation applications are usually top of mind. Commerical greenhouses can benefit from gas generator-driven combined heat and power (CHP) systems and again, Cummins has seen uptake in this sector with its recently launched HSK78G gas generator. Perhaps this is where we will see the initial wider adoption of natural gas power in agricultural settings, but we cannot ignore the benefits for farm machinery particularly as they’re a natural progression from the on-highway platforms already in service.
Could natural gas, and its renewable counterpart – biomethane, provide a platform for wider adoption of alternative fuels in agriculture?
Sustainability
Natural gas powered equipment can usually run on compressed natural gas (CNG), liquified natural gas (LNG) and biomethane, also known as renewable natural gas (RNG). Biomethane gives farmers the opportunity to generate fuel at the farm from widely available waste materials via an anaerobic digestor plant. Biogas from these digesters contains over 50% methane, which, when refined, produces the biomethane used to fuel compatible farm machinery.
In addition, transport costs and associated emissions relating to traditional fuel production can be significantly reduced, as the original biogas is produced from the farm’s livestock waste, crop residue, or even organic waste from local households and businesses. The material left over from the digestion process can be used to fertilise fields. In short, nothing is wasted.
Biogas is a key way for farms to decarbonise. Biomethane fuel derived from biogas produced at the point of use on the farm has a near zero CO2 profile. It is a renewable fuel derived from waste or energy crops that have pulled carbon from the atmosphere and, over time, would have released the same hydrocarbons as it rotted away. The fuel also produces comparatively less emissions at the point of use – natural gas powered engines, on average, produce lower levels of CO2 and NOx emissions than their diesel counterparts. For example, Cummins’ X12N natural gas engine produces up to 15% less CO2 compared to its diesel-powered equivalent.Â
Reduced fuel costs
As well as its environmental sustainability benefits, natural gas can provide financial benefits too. On average, natural gas is lower cost than diesel and in the long term, even less when produced on-farm. It’s an extremely attractive proposition for farms that are able and willing to invest in an anaerobic digestor plant.
Performance
As a fuel source, natural gas is around 25% less power dense than diesel, meaning a larger displacement engine may be needed for diesel-comparable power. However, Cummins’ advanced combustion technology is focused on delivering high power density while maintaining the fuel economy and flexibility benefits that natural gas provides.
Fuel flexibility
With natural gas engines, farmers can choose CNG, LNG or biomethane – a flexibility which allows machines to carry on working even in the event that a farm’s biogas production is disrupted. As well as its ability to meet global emissions regulations, natural gas enables CO2 reductions, giving farmers the option to decarbonise even further.
Case in point
Natural gas power is already making its way onto fields, certainly in Belarus where Gomselmash has launched its first natural gas powered harvester with a Cummins 350 hp ,12 litre engine. The harvester claims to have enough storage capacity for ten hours work at full engine load, or 12 hours at lighter duty operation, highlighting the viability of natural gas as a power option.Â
Cummins and Gomselmash worked closely to ensure that the 350 hp Cummins X12N integrated into the Palesse GS4118K combine would deliver near diesel-like performance. The ability to run on CNG, LNG and biomethane was a key consideration for Gomselmash. Its machines frequently operate in territories with challenging infrastructure and it was important to find a power solution that could be refuelled with either gas processed on the farm or available from vendors locally.
 Conclusion Â
Power for commercial and industrial machines is undergoing a period of change, which is likely to continue as we strive for increased performance and more productivity to feed a growing population, all while meeting increasing environmental sustainability needs.
The drive to reduce carbon emissions and adopt sustainable practices is of the utmost importance in agriculture, not just for governments and policy makers but for an increasing number of farmers too. Renewable fuel powered farm machinery is a major step in supporting farm decarbonisation and, in turn, can support sustainable food production. The smart use of waste is providing farmers with a unique opportunity to develop a truly circular economy. Against this backdrop, the benefits of biomethane for farmers are hard to ignore.
So, is natural gas the key to sustainable power for agriculture? It’s definately one alternative power option – but there’s an even bigger picture. Never before have we had the power diversity that exists today. In addition to natural gas, we’re seeing a diverse range of power sources including advanced diesel, hydrogen, electric and hybrid technologies being optimised for specific applications and sectors. Their success will depend on a range of factors including: government regulations, the availability of subsidies and the subsequent business case for agriculture given the heavy duty cycles in a large proportion of farm equipment. Investing almost $1bn in research and development ensures Cummins can deliver the diverse power portfolio agriculture needs.
