High-Efficiency Adsorption Chillers
PNNL - Pacific Northwest National Laboratory
High Efficiency Adsorption Cooling Using Metal Organic Heat Carriers
09/15/2010 to 09/14/2013
Buildings currently account for 72% of the nation's electricity use and 40% of our carbon dioxide emissions each year, 5% of which comes directly from air conditioning. Current building cooling systems run on electricity and use synthetic fluids, leading to large energy consumption and greenhouse gas emissions. Thermally driven adsorption heat pumps--which transfer heat energy from one location to another in a cooling and heating system--offer independence from electricity supply constraints because these technologies can be powered from the combustion of natural gas and solar and waste heat. In addition to providing efficient space cooling and heating, these heat pumps can heat water. However, the these systems' development has been hindered by low energy efficiency and bulkiness that are due to the limited sorption capacity of the adsorbent material--resulting in increased assembly time and high system costs.
Project Innovation + Advantages:
PNNL is incorporating significant improvements in materials that adsorb liquids or gases to design more efficient adsorption chillers. An adsorption chiller is a type of air conditioner that is powered by heat, solar or waste heat, or combustion of natural gas. Unlike typical chillers, this type has few moving parts and uses almost no electricity to operate. PNNL is designing adsorbent materials at the molecular level with at least 3 times higher refrigerant capacity and up to 20 times faster kinetics than adsorbents used in current chillers. By using the new adsorbent, PNNL is able to create a chiller that is significantly smaller, has twice the energy efficiency, and lower costs for materials and assembly time compared to conventional adsorption chillers.
If successful, PNNL would produce a smaller, lighter, and cheaper air conditioning unit that could significantly change the existing chiller market for commercial buildings.
Waste heat or solar heat-based technology for air conditioning would help reduce reliance on fossil fuels.
Widespread adoption of this technology could reduce energy consumption for air conditioning of buildings--providing consumers with cost savings on energy bills.
Greater use of heat-based technology for air conditioners would reduce greenhouse gas production related to electricity generation and could increase demand for solar power--increasing use of renewable energy for cooling.