Following a small investment, a Tipperary meat plant discovers unquestionable benefits of energy recovery. Read on to find out more…
As part of the ABP meat processing group, ABP Cahir is committed to actively searching for sustainable sources of heat and power to operate their plant. Their sustainability policy is “Doing More with less”. So, in 2013, when they installed an Ingersoll Rand Nirvana R45n Air Compressor and Air Treatment equipment package to provide compressed air to the CPM department, they included an Air Compressor Energy Recovery System in the equipment scope of supply. The CPM Plant is where raw meats, like beef and pork, are taken in and packaged for retail. There are nine production lines in the packaging hall from here products is sent to markets across Europe.
The compressor ERS was connected to a calorifier which provides hot water for washing down – an essential sanitation process in a food processing plant.
The Nirvana Variable Speed Drive Compressor, rated at 7.42 m3/min, was sized to allow for peaks in plant air demand and is operated 12 hrs per day 6 days per week. Like many compressor applications with peaks and troughs in demand, the average compressor load can be low. In this case, the unit operates at an average load of 23% which, at first glance, is not an ideal scenario for energy recovery. However, based on a recent two-week trial carried out on the system by the team in Cahir, we can see that there are savings to be made even when a compressor is running at low load and a relatively low number of hours p.a. Although the savings are small, if viewed from a return-on-investment perspective, the initiative was a fantastic success!
Trial Results
| ERS Investment Cost | Compressor Load Capacity Avg | Water flow | Water temp IN | Water temp OUT | Running Time | Recoverable Energy |
| €1,380.00 | 23% | 1.98 m3/hr | 37.7 °C | 42.6 °C | 12hrs/day | 11.31 kwh |
The data above reveals that the heat recovery from the units is 11.31kWh or 42,345kWh per year. With a Gas unit price of (0.028c/kWh) and Gas Boiler efficiency of 85%, this represents a gas saving of €1,394.00 P.A. The return on Investment is 1.01 Years. Total saving to date (and counting) is almost €11,152.00. This is almost 50% of the original cost of the air compressor!
| Savings | Return on Investment | Total savings to date |
| €1,394 p.a. | 1.01yrs | €11,152. |
But the story does not end here. Appreciating the viability of energy recovery, even where compressed air usage is small, ABP Cahir has now decided to retrofit an Energy Recovery System to their Ingersoll Rand R75n Plant Air Compressor.
Projected Savings from R75n Compressor:
| ERS Investment CostPlus Retrofit Pipe work | Compressor Load Capacity Avg | Water flow | Water temp IN | Water temp OUT | Running Time | Recoverable Energy |
| €4,215.00 | 87% | 4.09 m3/hr | 38.7 °C | 50.0 °C | 12hrs/day | 54.68 kwh |
Kw/hrs= Specific Heat Capacity 4.26 x Water Flow Rate 1.136lts/s x Delta T 11.3c
Savings a bit meatier!
The potential annual energy recovery is 204,739.77 kwh. With a Gas unit price of (0.028c/kWh) and Gas Boiler efficiency of 85% this represents a potential gas saving of €6,744.00 P.A. The return on Investment is 7.5 months and 10 Year projected savings are €67,443.00.
| Projected Savings | Return on Investment | Projected savings in 10yrs |
| €6,744 p.a. | 7 ½ months | €67,443.00 |
Alex Mühlwald, Engineering Manager at ABP Cahir, said “We’ve carried out major energy saving projects in the plant over the past number of years and projects such as the compressor energy system will help us achieve the marginal gains that we look for year on year. We are delighted to partner with O’Neill Industrial to bring these initiatives to fruition.”
Commenting on the outcome, Austin O’Neill, O’Neill Industrial, said “The overwhelming majority of the energy used to run a compressor is converted into heat through the compression process, and this heat is normally exhausted to atmosphere or left to absorb into the cooling water cycle. A heat recovery system will reduce your energy costs. But you don’t need to wait until you install a new compressor to achieve energy savings. Retrofitting is an ideal way to achieve long-term cost benefits from a low-cost investment.”
EXEED Certified grant
SEAI provide grant support for energy investment projects which follow the EXEED Certified standard for Excellence in Energy Efficient Design. The EXEED standard encourages innovation in design projects to help future-proof the investment, by optimising energy performance, reducing operational energy costs and carbon emissions, improving competitiveness and demonstrating a commitment to sustainability, which could also bring a reputational boost.
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