The official first day of fall was just a month ago and temperatures are already starting to drop. This past winter, extreme cold across the country created such high demand for natural gas that several regions faced shortages, resulting in unprecedented rate hikes from utility companies. Because energy consumption typically represents 70 percent of the overall cost of a compressed air installation, now is the time to consider innovative ways to cut your energy bills.
Energy Recovery Meets Education
Reusing the waste heat from air compressors is a no-brainer for manufacturers who want to defray the costs of other necessary production processes that require hot water. With energy recovery, water flows through a heat exchanger that captures the heat of compression from an Atlas Copco air compressor, which heats the water to the desired temperature. Manufacturers can typically recover 80-100 percent of the original electrical input energy used to power the air compressor using energy recovery.
A packaging production plant located in Northern Ireland took their energy recovery project one step further by donating waste heat to a neighboring college via pipework buried underground. The heat is delivered directly to the college’s central heating system and has already helped the college save nearly $62,000 on its annual heating bill and 200 metric tons of CO2.
How it Works
The packaging company specializes in the production of rigid packaging containers supplied to the food industry in Great Britain and Ireland. Compressed air is essential for all of the company’s production processes and is supplied by Atlas Copco oil-free, water-cooled Z-range compressors – with their outputs optimized by a central controller. The compressors’ water-cooling systems provide a substantial addition to the heat supply to the nearby school.
Air drawn into a compressor contains water vapor. Heat stored in the vapor is released through condensation in the inter- and after-cooler of the compressor. The condensation heat contained in the input air is equivalent to 5-20 percent of the electrical input energy. Atlas Copco’s Z-range of oil-free screw compressors with energy recovery use the waste heat to recover 80 to 100 percent of the electrical input energy, depending on the site conditions.
The rapid sequence of heating and forming plastic materials requires equally fast cooling of the molten polymers. The cooling is done through a large battery of condenser cooling fan units, in addition to the water cooling systems on the compressors, which extract the heat in the form of hot water at 176 degrees Fahrenheit, which is then delivered to the school via underground pipes.
Innovative Partnership Saves Energy, Reduces Environmental Impact
The partnership between the manufacturer and the local college is thought to be the first of its kind and was aided by matching funds from the local Department of Education. If you have a great idea for an innovative way to reduce your plant’s environmental impact while benefitting your local community, share it in the comments below. You may also enjoy the following articles:
- Replacing Surface Aerators with Turbo Blowers for Energy Savings
- Looking for a Good Excuse for an Equipment Upgrade?
- Unlock Your Compressed Air System’s Predictive Maintenance Potential
Source: Compressed Air Blog