NZEB - 'Nearly Zero energy Building'

Gas absorption heat pump (GAHP)

• A water and ammonia solution in combination with a condensing gas burner is used in a thermodynamic cycle to capture renewable environmental energy.

• A low electrical consumption of less than 0.9kw for every 38kw of heat combined with a low gas consumption delivers a GUE as high as 169%

• The ammonia and water solution works in a sealed circuit and is considered a natural refrigerant, with no requirement for F-Gas maintenance, ensuring zero impact on greenhouse gas emissions.

• The heat generated by the thermodynamic cycle is passed to a water heating circuit to provide heating and hot water production. Cooling is also possible with a GAHP.

Gas fired heat pump (GFHP)

• A GFHP uses a gas engine to drive an internal compressor and evaporation cycle using a refrigerant gas, heat generated by compressing the refrigerant is passed to the heating outlet via a VRF system.

• Electrical input required is extremely low with only a single phase standard 3 pin connection required. This makes a GFHP ideally suited for areas where an increase in electrical capacity is not available.

• A GFHP is particularly suitable on sites where there is a requirement for heating, hot water and cooling or a combination of these. Both natural gas and LPG can be used to fuel the heat pump.

• The waste heat generated by the engine is harvested to supply hot water and help the defrost cycle. This ensures there is no interruption to the hot water demand cycle.

Combined heat and power (CHP)

• CHP also known as "Co-generation", is the simultaneous production of electricity and heat usually in the form of hot water or steam from a primary fuel such as natural gas

• CHP is particularly suitable on sites where there is a high demand for both electricity and steam or hot water

• Natural gas supplies a gas engine which in turn is connected to an electrical generator which produces on site electricity. The heat generated by the turbine or engine during the combustion process is harvested to meet the thermal energy requirements of the facility.

• Onsite generation reduces energy lost in transmission from source to site. By extracting both heat and electricity from a single unit of fuel, energy efficiency of up to 90% can be realised, compared with roughly 50% efficiency from the electrical grid when transmission and distribution losses are factored in

Gas boilers & solar PV

• Traditional high efficiency gas boilers can be combined with gas driven renewable technologies and Solar PV panels, to meet the changing building regulations, while capturing all the traditional benefits of a gas boiler system (low capex, security of supply, on-demand hot water) while future proofing for renewable biomethane and hydrogen

• Incorporating a hybrid gas heat pump/ gas boiler/PV system is particularly suitable on sites where there is a demand for both hot water and electricity on site

• Electricity is generated on site using panels each with a peak performance >400Wp. Using natural gas and PV to generate the energy onsite, can often deliver lower CO2 emissions compared to other technologies

• Installing gas powered technologies means you are able to benefit from the ongoing decarbonisation of the gas network as greater volumes of renewable gases such as biomethane and hydrogen are introduced