DENSO is world-renowned for its car parts and systems – but did you know that the company also develops a wide range of advanced technologies for home and industry? Although non-automotive products today account for around 2% of DENSO Corporation’s global revenue, there is a high passion and ambition to grow this business area in the coming years. DENSO strongly believes that the key growth enablers to do so are:
- Existing advanced technology derived from Automotive
- DENSO global presence to manufacture products and to provide services to our customers anywhere.
Heating homes more efficiently with the CO2 Heat Pump
DENSO Industrial Solutions specialises in products that apply unique technology to a range of cooling and heating solutions for home and industry. As a result we save energy needed for cooling and heating and herewith save cost for our customers to operate the product and contribute in reducing C02 emissions.
One example is the DENSO CO2 Air to Water Heat Pump – successfully delivering domestic heating and hot water with less harm to the environment.
An air to water heat pump is a very efficient device used for house heating and hot water production. Its heat energy output is about three to five times as high as the electricity input. The technology is similar to that of an air conditioning system: it uses a refrigerant cycle with a compressor and heat exchangers to extract heat from the ambient air and transfers this heat to water.
When designing the Air to Water Heat Pump, DENSO’s engineers wanted to achieve heating comfort and efficiency in a more environmentally responsible way – echoing DENSO’s Vision 2015 of a greener and safer future society.
The first breakthrough was to change the refrigerant. Typically heat pumps use a synthetic refrigerant gas such as R410A, which has a Global Warming Potential (GWP) of 1725. To improve on this, DENSO’s Air to Water Heat Pump was the world’s first heat pump to feature the natural refrigerant carbon dioxide (CO2) – which has a GWP of just 1.
Another design “break- through” is the DENSO Patented ‘Ejector Cycle’ technology, which optimizes the compressor efficiency. It recovers energy normally lost during the vapor compression cycle by increasing the compressor intake pressure.
DENSO first introduced CO2 refrigerant to its Air to Water Heat Pumps in 2001, in Japan. Known as ‘Eco-Cute’, the product‘s improved energy efficiency meant that less domestic electricity was required. As a result the innovation won six globally recognised energy and environment awards, including the 2002 EPA Environmental Climate Protection Award from the U.S. Environmental Protection Agency.
DENSO’s CO2 Air to Water Heat Pump was first introduced into Europe in 2009 and set a new standard for compact size, light weight and low noise. It is supplied as original equipment to heat pump manufacturers. DENSO CO2Heat Pumps are now starting to be used in homes across Europe, supplying efficient, eco-friendly under-floor heating and hot water.
DENSO Electronics cooling: ‘air conditioning’ without a compressor
DENSO, as the global leader in automotive thermal systems, uses its advanced Heat Exchanger technology to develop state-of-the-art cooling equipment for electronics. One example of this is the indirect cooling of equipment contained in cabinets by means of cold air.
DENSO introduced this ‘Thermosiphon’ technology to the global leader in telecom networks for the purpose of cooling radio equipment held in Radio Base Station (RBS) cabinets. This technology allows for extremely effective cooling performance while eliminating the need for a compressor. This minimises maintenance costs as well as the risk of system downtime caused by possible moving part malfunctions, whilst optimising the energy efficiency of the RBS itself.
Thermodynamics in action
The Thermosiphon process uses the basic laws of thermodynamics and gravity to create movement of a heated liquid or gas:
- When a liquid or gas is heated, it gains kinetic energy from the heat source and becomes excited. As a result, the liquid or gas becomes less dense, expands, and therefore rises
- In contrast, when a liquid or gas is cooled, energy is extracted from the molecules and the water becomes less active. It also becomes more dense and tends to ‘sink’. This effect explains the circulation of the liquid or gas without a pump or compressor
In DENSO’s case, the Thermosiphon system comprises of one or more sets of heat exchangers, filled with refrigerant. The energy source for this process is the waste heat from the electronic equipment inside the cabinet.
Even more applications
Another example of DENSO electronics cooling without a compressor is the Power Unit Cooler (PUC).
The PUC was originally developed by DENSO for a Japanese manufacturer of elevators, for cooling high power transistors (IGBTs). The PUC comprises of a refrigerant-filled cold plate and a condenser. It has a much higher cooling capacity than traditional, water-filled cold plates.