Energy and Milking Efficiency
Why is this research important?
The European Union (EU) aims to reduce greenhouse gas emissions by 55% from 1990 to 2030. As agriculture is Ireland’s largest contribution sector to greenhouse gas emissions, accounting for 37.1% of emissions in 2020, it is also a key focus sector for reductions.
Irish policy aims to reduce emissions in the agricultural sector by 25% by the year 2030. It is also recognised that the agricultural sector will have a part to play regarding the decarbonisation of the energy generation sector with targets to reduce agricultural energy use by 20% and generate at least 20% of energy consumed from renewable sources by 2030.
To encourage the uptake of renewable energy generation by farmers, the Irish government has introduced a clean export tariff that will guarantee payments to small generators of renewable energy for electricity exported to the national grid for 15 years. Eligible installations must have a rated power output of 6 to 17 kilowatt peak power (kWp) for single phase systems or 11 to 50 kWp for three phase systems.
Against the backdrop of an increase in national herd sizes from an average of 58 dairy cows in 2010 to 90 dairy cows in 2020, a number of significant issues have become more prevalent. The milking process accounts for a large proportion of working times on dairy farms representing 31% of the work week. The difficulty in recruiting appropriately skilled labour is increasing and poses a major challenge at farm level. The uncertainty generated by these issues has highlighted the need for an in-depth understanding of energy and milking efficiency on dairy farms and the relationship between these two factors.
What the research tells us
The work programme of this research area is focused on the following objectives:
- Quantify the energy use of Irish dairy production systems through intensive on-farm auditing and remote data collection
- Analyse energy use within Irish animal production systems, explore farm to farm variation and identify hot-spots of energy consumption
- Evaluate the potential for renewable energy use in Irish dairy production systems using models
- Use farm energy models to simulate the technical, environmental and economic effect of renewable energy deployment on Irish dairy farms
- Increase milking parlour throughput and cow comfort by applying novel cluster removal strategies, pre-milking stimulation and pulsation parameters during milking
- Benchmark milking efficiency levels on commercial Irish dairy farms and assess the effect of operator, management and infrastructure on milking efficiency
- Quantify the farm and parlour management practices, parlour technologies, milking management practices and somatic cell count (SCC) control strategies used on Irish dairy farms
Results
Energy research results
- The energy use benchmarks for herringbone and rotary parlours were updated to reflect post-quota production systems. The energy use for rotary parlours was 9% lower than that of herringbone parlours (9 watt-hour per unit weight of milk produced (Wh kg/Milk) for rotary vs. 32.8 Wh/kgMilk for herringbone). We found that the milk cooling system (33% of total), water heating system (31% of total) and the milking system (16% of total) were the largest energy users, in agreement with previous literature
- For both milking system types investigated, we identified that as milking efficiency increased, energy efficiency also improved. For example, the most efficient herringbone farms in terms of milking efficiency (top 10%), consumed 11 kWh less energy per tonne of milk harvested than the least efficient herringbone farms (bottom 10%). Hence, we reported that higher rates of milking efficiency translated to improved energy efficiency regardless of parlour type
Milking research results
- For herringbone farms, the average milking efficiency on Irish farms was 94 cows/hour, 73 cows/operator per hour and 1,012 litres/hour. In comparison, rotary farms achieved an average milking efficiency of 170 cows/hour (+81%), 132 cows/operator per hour (+89%) and 1,534 litres/hour (+51%). Effects of automation and operator efficiency on milking efficiency were found to vary by milking system size and type
- The most common parlour types on Irish dairy farms were swing-over herringbones (59.3%) and herringbones with recording jars (21.8%). The most common parlour technologies were in-parlour feeding systems (82.9%), automatic washers on the bulk tank (71.4%), automatic cluster removers (57.2%) and entrance and exit gates controlled from the pit (51.7%). We also found that the majority farmers were relatively content in their careers, though there were stressors including the challenges of prudent antibiotic use and controlling farm-level SCC. Veterinary professionals, farming colleagues and processor milk quality advisors were the most commonly utilised sources of advice for SCC management (by 76.4%, 49.6% and 38.6% of respondents, respectively)
Outputs
Contacts
John Upton: John.Upton@teagasc.ie