Compressor Heat Recovery
alternative practice names:
Refrigeration Heat Recovery; Heat Recovery Unit; Fre-Heater®; Therma-Stor®
Compressor heat recovery systems allow the dairy farm to utilize waste heat from the milk cooling process to pre-heat hot water before it enters the water heater. This results in significantly less energy (propane, natural gas, electricity, etc.) required to heat hot water used for cleaning and other processes.
Water is typically pre-heated to 110°F to 140°F by compressor heat recovery units, and the energy used to heat water can be reduced by 30-60%.
The most common type of compressor heat recovery system consists of an insulated storage tank, similar to a hot water storage tank, that contains a heat exchanger to capture waste heat from the refrigerant loop after it has been extracted from the milk entering the bulk tank. The heat recovery storage tank is connected to the primary hot water storage tank, where it is heated to the desired set point temperature before being utilized.
When used, in what regions in the U.S. is the practice found:
Northwest, West, Upper Midwest, Southwest, Northeast, Southeast
FARM SIZE
When used, typically found on farms of the following sizes:
All Sizes
Practice Benefits
Increased profitability: Heat recovery reduces energy costs. Additional benefits include improving the efficiency of the refrigeration system, which can extend the life of compressors and other components. Additionally, the life of the water heater can be increased.
Implementation Insights
Site-specific or Farm-specific requirements
Size and location: Compressor heat recovery units are compatible with most dairy farms, assuming they have space to accommodate the compressor heat recovery unit. The heat recovery tank should be properly sized by the equipment vendor and should be installed as close as possible to the bulk tank compressors to maximize the heat transfer.
Required Capital Expenditures (CapEx)
Compressor heat recovery system: This typically includes a storage tank with a heat exchanger and any labor costs required to install it.
Power supply upgrades: Compressor heat recovery units typically require 240-volt single-phase power. A dairy equipment vendor can typically provide a detailed quote and the installation process is usually straightforward.
Required Operational Expenditures (OpEx)
Maintenance: Ongoing maintenance expenses are minimal and include occasionally replacing low-cost parts as needed. Energy cost savings achieved by installing a compressor heat recovery system will greatly outweigh any costs and labor for maintenance.
Implementation Considerations
Maintenance protocol: Recommended annual maintenance for compressor heat recovery units includes checking anode rods and replacing as necessary, draining and backflushing the heat recovery tank to remove loose scale collected at the bottom of the tank, manually checking the temperature relief valve to ensure it is functional, checking all fittings and valves for water leaks, and observing the operation of all controls connected to the heat recovery system and refrigeration system.
Financial Considerations and Revenue Streams
PROFIT POTENTIAL
Installing a compressor heat recovery unit can result in significant cost savings for heating water for a dairy farm. It is important to speak with an authorized equipment dealer to discuss your specific situation and determine viability. For farms that use natural gas or electricity to heat water, rebates are sometimes available through the natural gas or electric utility company.
FEDERAL COST-SHARE AND CONSERVATION FUNDING
Funding is available for this practice through USDA's Natural Resources Conservation Service (NRCS) Environmental Quality Incentives Program (EQIP) On-Farm Energy Initiative.
Related EQIP Practice Standard: Energy Efficient Agricultural Operation (374).
Notes:
An Agricultural Energy Management Plan (AgEMP), or other qualifying energy audit, needs to be completed before applying for EQIP assistance.
Check with the local NRCS office on payment rates and practice requirements relevant to your location.
The USDA Rural Development Rural Energy for America Program (REAP) also offers competitive grants and loan guarantees for installing energy efficiency projects.
Additional Resources
Article: Energy Conservation on the Farm: Refrigeration Systems (University of Wisconsin)
Book: Dairy Farm Energy Efficiency (ATTRA)
Video: Energy Efficiency: Heat Recovery Systems (Innovation Center for U.S. Dairy)
Environmental Impacts
REDUCES FARM GREENHOUSE GAS FOOTPRINT
Improving energy use efficiency reduces a farm's greenhouse gas (GHG) footprint. Since energy production typically involves processes that emit greenhouse gases like carbon dioxide and methane, cutting energy use directly lowers the GHG footprint of the farm.
Alignment with FARM Program
FARM Environmental Stewardship (ES) V2-V3 Alignment
FARM ES captures a farm's energy usage and calculates the associated GHG emissions based on regional energy production and transmission averages. Any practice that reduces farm energy consumption will directly lower the farm's GHG footprint. The reduction in GHG emissions is particularly pronounced in regions where a larger proportion of energy is derived from coal, natural gas, or other fossil fuel sources, as these energy types have higher carbon footprints compared to renewable energy sources.
Contents
We're always eager to update the website with the latest research, implementation insights, financial case studies, and emerging practices. Use the link above to share your insights.
We're always eager to update the website with the latest research, implementation insights, financial case studies, and emerging practices. Use the link above to share your insights.
Compressor heat recovery systems allow the dairy farm to utilize waste heat from the milk cooling process to pre-heat hot water before it enters the water heater. This results in significantly less energy (propane, natural gas, electricity, etc.) required to heat hot water used for cleaning and other processes.
Water is typically pre-heated to 110°F to 140°F by compressor heat recovery units, and the energy used to heat water can be reduced by 30-60%.
The most common type of compressor heat recovery system consists of an insulated storage tank, similar to a hot water storage tank, that contains a heat exchanger to capture waste heat from the refrigerant loop after it has been extracted from the milk entering the bulk tank. The heat recovery storage tank is connected to the primary hot water storage tank, where it is heated to the desired set point temperature before being utilized.
Practices and technologies
Compressor Heat Recovery
alternative practice name:
Refrigeration Heat Recovery; Heat Recovery Unit; Fre-Heater®; Therma-Stor®