Zero CO2 – Site Generated Solar Hot Water
One the largest consumers of energy within any house is the heating of domestic hot water to service the kitchen and bathrooms. As part of the sustainable development, solar hot panels where mounted on the south-facing roof of the house to convert sunlight to domestic hot water. The south-facing roof structure provides optimum solar orientation without compromising the building appearance. A 6kW wind turbine in the garden produces all the other required domestic electric, much of which is exported back to the grid to create a small income stream from the renewable installation.
Zero CO2 Site Generated Renewable Electricity
A 4kW photovoltaic array mounted in the wildflower meadow in the garden produces most of the required domestic electric.
Ground Source Heat Pump Under Floor Heating System
The passive solar design layout to the super insulated building fabric with thermal mass reduces the heat losses to a minimum creating considerable thermal inertia eliminating the need for a full conventional central heating system. No central heating boiler run of fossil fuels has been required. A ground source to water heat pump extracts the latent heat below the ground and invests it in to a thermal mass water store cylinder via a heat exchanger to provide hot water to run an under floor heating system.
Zero CO2 – Bio-Mass Secondary Heating System
A very efficient 2 to 4 kW efficient space heater using biomass fuel from the land provides a social focus to the kitchen / dining / living room and compliments the heat gains from the sun, the occupants, the household appliances and the re-circulated heat from the heat recovery ventilation system.
Low Energy Appliances
All appliances have been carefully considered to eliminate unnecessary electrical demand and to optimize the efficiency of the essential items (cooker, fridge, low energy lighting etc). All selected components are category A* rated for maximum efficiency and minimal electrical draw when in use.
Mechanical Ventilation With Heat Recovery
For winter months when the outside air is cold relative to the required inside temperature, a whole house clean air comfort ventilation system is fitted with heat recovery (to preheat incoming cool fresh air with outgoing warm stale air) is used to reduce space heating requirement to a minimum.
Household and garden non-potable water requirements are met by collecting rainwater from the main roof via galvanized steel gutters and downpipes and storing it in water butts and a ‘Rainharvester’ underground storage tank. Water from underground storage is filtered and used for flushing toilets and the washing machine. The water butts are used for garden irrigation. Water efficient flush toilets have been used along with air rated flow restricted taps a maximum flush of 4 litres. Water use is being monitored to ensure a non-wasteful system of use is maintained.
Healthy Internal Environment
Scatter rugs over stone tiled and waxed timber boarded floors, organic non-volatile solvent paints, avoidance of formaldehyde and other toxic equivalents combined with natural materials and summer natural ventilation and a winter heat recovery mechanical ventilation system provides a healthy internal air quality.
Kitchen waste and garden debris material is composted until dry and inert and then returned as a valuable non-toxic fertilizer to the food growing areas of the garden and greenhouse.
Text by Andrew Yeats Eco Arc Architects Photos by 3B.