Beyond energy efficiency
Simply delivering energy-efficient products as its contribution to reducing the threat of climate change was not enough for Sanyo, which has adopted the Think-Gaia concept to direct its future development.For nearly 200 years industrial societies have been burning fossil fuels at a rate that is now acknowledged as upsetting the balance of the planet. In the latter part of last century, as Hugh Dixon, European marketing manager with Sanyo, explains, mankind’s pursuit of convenience and material comforts has left indelible stains such as global warming and environmental destruction.
Think Gaia It was against that background that Sanyo, which has always had a strong environmental focus, took the decision in 2005 to base its corporate philosophy on the concept of ‘think Gaia’. Under this vision Sanyo has committed to using its global resources and skills to develop solutions for a sustainable coexistence. Gaia was the mythical goddess of the earth, and the Gaia concept that is gaining momentum today is based around the belief that living organisms on the earth affect the nature of their environment. The Gaia concept put forward by English scientist James Lovelock in 1979 proposed the idea of earth as a living, green organism where mankind and all living things live in harmony. A significant manifestation of this ethos is the Solar Ark in Japan, the world’s largest solar power station, with over 5000 photovoltaic cells capable of an electrical output of 630 kW and generating around 530 MWh of electricity a year. It is used to supply a Sanyo production plant. Sanyo’s commitment to thinking Gaia has led to the pledge that the company will only develop products that are absolutely essential to life and the Earth. Air conditioning, space heating and water heating are clearly seen in that light and have benefited from investment not only to reduce their energy consumption but also to supply much of that consumption using renewable energy.
Solar-powered services It is a philosophy that has seen Sanyo move on from heat pumps (both air and water source) and solar photovoltaics to solar-powered air conditioning, heat pumps and water heating. Graham Wright, product manager for Sanyo Air Conditioners, explains, ‘Our pioneering spirit is set to revolutionise the air-conditioning industry, with 2007 seeing the development of a raft of ground-breaking products — including an innovative solar PV air-conditioning system and the CO2 heat pump.’ The combination of efficient air-conditioning technology and solar PV leads to quite spectacular performance. Graham Wright says that COPs can be up to 7.0 at part load and that it is theoretically possible to achieve as high as 24. Solar power can be added to any of Sanyo’s range, including VRF, GHP (gas-fired heat pump) and split systems. A PV split system has an integrated power inverter to enable seamless operation, whatever the source of power — including three or more PV panels located to maximise power input. To ensure that energy is used efficiently, these systems use a high-efficiency rotary compressor that includes 2-stage compression, DC brushless motor and inverter drive and an extremely efficient motor with high-power magnets. Sanyo has also brought novel thinking to producing hot water using heat pumps. For those familiar with this kind of technology, a COP of 3.75 to produce water at 65°C using energy extracted form outdoor air at 7°C might seem unlikely. However, Sanyo uses carbon dioxide as the refrigerant, which has much better performance than HFCs at these temperatures. The carbon-dioxide charge is contained in the outdoor unit, with heat transferred to a storage tank by heated water. Applications include space heating and domestic hot water. For maximum efficiency, the CO2 ECO uses a rotary 2-stage compression system.
Gas-engine heat pumps Another concept presented as part of Sanyo’s think-Gaia approach is its heat-pump VRF air-conditioning system driven by a gas engine and which can provide both heating and cooling. This concept is particularly useful if electricity is in short supply, but GHP VRF is increasingly specified for its environmental merits. Vincent Mahony, general manger for Sanyo air conditioners in Ireland, explains that in Japan, GHP VRF systems have already gained 48% of the VRF heat-pump market — and he expects similar popularity in Europe. The latest GHP VRF systems use R410A, enhanced heat exchangers and an engine-management system — which, together, have improved efficiency by 19%. Only a small amount of electricity is required (for start up and fan operation). The design eliminates the need for a defrost cycle, so performance and efficiency are maintained at low outdoor temperatures. The gas engine drives the compressor directly, rather than using an electric motor. However, waste heat from the engine can also be exploited when required.
Landmark project A landmark project for GHP VRF is the 5-star Fota Island Hotel in Cork, Ireland. The installation comprises nine gas-engine units on the roof delivering 504 kW of cooling to 139 indoor units. The outdoor units can provide heating and cooling at the same time. Alistair Howard of consultants E. G. Pettit & Co. explains, ‘We reviewed a number of alternative solutions for hotel air conditioning. A natural-gas-operated heat-pump system was identified as providing energy-saving heat recovery, automatic heating and cooling changeover, simultaneous heating and cooling, BMS and reception-desk controls interface, a low running cost and a short-term payback. Sanyo’s environmental perspective is broad, as Graham Wright explains: ‘Sanyo is the only leading Japanese air-conditioning manufacturer to offer a full portfolio of electric heat pumps, gas-engine heat pumps, heat recover, solar PV, fuel cells and Micro CHP. ‘Rather than being diversification, heating products such as the CO2 Eco heat pump are just meeting a need for environmental units, following the think-Gaia concept which is driving environmental sustainable product development throughout the Sanyo Corporation.’
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