The focus on energy efficiency and corresponding cuts in carbon dioxide emissions is part of a new strategy by Mitsubishi, one of the UK’s leading suppliers of heating and air conditioning systems, to promote its heat pump technology.
The company recently launched its "green gateway initiative" in response to the increasing number of government policies aimed at reducing the embedded energy of buildings.1Heat pump technology is more energy efficient than conventional gas boilers and air conditioning systems because it combines heating and air conditioning systems.
But Mitsubishi still advocates the use of refrigerant R410a, which is a blend of HFC-32 and HFC-125. These greenhouse gases are 550 and 3,400 times more potent respectively than CO2.
An EU regulation to control HFCs and other fluorinated gases was adopted last year. It sets leakage inspection standards for equipment that contains HFCs, including air conditioning systems. It also requires stricter standards for servicing, handling and labelling equipment containing the gases.
A typical heat pump can generate three times more energy than it uses. It turns naturally occurring heat in the ground or air into useful high-temperature heat, or visa versa to provide cooling, using the same principles as a refrigerator.
The pumps are commonly used in Sweden as a primary source of heating and hot water, and the technology is already well known in the air conditioning market. It is increasingly used in commercial buildings, but is little used in homes.
Mitsubishi claims 720,000 tonnes of CO2 per year could be saved by 2016 if all new homes replaced conventional gas boilers with the pumps. If it replaced just 10% of the 1.6 million gas boilers sold each year for existing properties, the potential savings would, it says, increase to more than two million tonnes.
But a comparison based on greenhouse gas emissions, taking into account HFC leakage over the equipment’s lifetime, would have provided a broader view of the global warming impact of such systems across their life cycle.
In the 1990s, HFC producers and suppliers of ‘natural’ refrigerants, such as ammonia and hydrocarbons, fought a marketing battle over which system had the lower global warming impact. The debate led to the creation of the concept of ‘total equivalent warming impact’.
Mitsubishi is to stop selling ‘cooling only’ products, although it has yet to set a timetable for their withdrawal. In February, it surprised the air conditioning industry by questioning whether the rapid growth of residential systems was "necessary" or "sustainable".
Instead it wants to persuade the market of the environmental benefits of its "Lossnay" technology. This reduces overall energy costs by using extracted stale air to heat or cool incoming fresh air. Depending on ambient heat loads, the system can be configured to start heat recovery in cooling mode at external air or ground temperatures above, for example, 21°C; be in ‘free cooling’ mode - not using any electricity - between 10-20°C; and recover heat when temperatures fall below 10°C.
Price quotations will include whole-life costs and will compare running costs, CO2 emissions and potential CO2 savings with those of more conventional systems.
The company has also drawn up list of ‘green’ products that have at least a B-rating under the EU energy labelling scheme, and plans to phase out manufacture of lower-rating products. Sales staff will be rewarded for increasing sales of listed products.