Presentation on theme: "NET ZERO HOUSE Etienne Hentzen Mark Horgan Mark Lewis Grant MacGregor Darren Tannock."— Presentation transcript:
NET ZERO HOUSE Etienne Hentzen Mark Horgan Mark Lewis Grant MacGregor Darren Tannock
RECAP Ventilation system Energy management Rainwater harvesting Solar thermal collectors Under floor heating
GROUND SOURCE HEAT PUMP The overall hot water and space heating requirement of the dwelling is 8,500 kWh P.A. With the use of Solar thermal collectors this is reduced to 2579 kWh P.A. A ground source heat pump shall be used to cover the rest of the heating requirement WW3500 by Calorex provides a CoP of 3.64 when taking water from 10 degrees to 55 degrees. A conservative CoP value of 3 was taken in calculation. The heat pump can supply 2579kWh water heating for 859kWh of electrical energy P.A.
OVERALL ENERGY PROFILE Energy (kWh/day)JanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember Heating Demand Solar Thermal Energy Gain Heat Pump Demand Electrical Appliance Demand7.6 Total Electrical Demand Solar Energy Gain Wind Energy Gain Total Energy Gain Excess Energy Gain The energy demand is shown in sequence per month. At no time does demand exceed gain.
OVERALL ENERGY PROFILE
The house can sustain a 3-7 days storage using a Raylite M-Solar 2V 1380Ah battery. This allows for building autonomy on days where there is no wind or sun. Storage Raylite M- Solar 2V 1380AhJanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember Total Electrical Load Days of Storage Required Battery capacity (kWh)66.24 Battery capacity at 80% DOD (kWh)53 No. Of Batteries Required No. Of Days Storage Achieved
OVERALL ENERGY PROFILE Taking into account all heat and power generation technologies the demand of the house is 3635kWh/year. This is equivalent to 20 kWh/m2 floor area per year. Energy kWh/PA Demand Generated Excess
EXCESS ENERGY In this house we generate much more energy than we need. Using the Feed In Tariff we can acquire wealth through generation and exporting energy. It is possible to calculate the pay back time of the renewable energy generation technologies given these average figures.
ENERGY SYSTEMS PAY BACK TIME The cost of all energy systems technologies within the house was totalled up and weighed against their savings. The pay back time for the energy systems within the building is years After the technologies have paid for themselves they will generate £4000 income for the family through the Feed In Tariff and energy savings. Money Spent £ Energy Systems65750 Money Saved £/PA Materials Electricity Heating Energy Systems Total Buy back time (Years)16.22
BUILDING RATING BREEAM Ecohomes 2006 (replaced by CfSH in England/ Wales, still used in Scotland) Pre-Assessment Tool used Energy values obtained from SAP worksheet, 2005
BREEAM ASSESSMENT BREEAM Element Library INSULATIONCLADDINGPLASTERBOARD A+ A
WALL INSULATION PROFILE U-Value = 0.13 W/m 2 K Thermal lag time = hours Advantages: Positive Carbon Value- straw bale absorbs carbon in growing process Thermal properties of a heavyweight structure (heat flux time delay) Low sound transmission (thickness of straw bale acts as excellent sound dampener Airtight and vapourtight as per PassivHaus standards
HEAT LOSS Heat Loss Parameter = (Fabric loss+ Ventilation loss)/ Floor area =( W/K) / 180m 2 = 0.64 W/m 2 K 0.64 < 1.1 HLP for maximum Ecohome Score
ECOHOMES SCOTLAND 2006
ASSUMPTIONS Zero-carbon emissions Drying space provided indoors All appliances (fridges, washing machines, etc.) A+ energy rating Efficient external security lighting with day-light/ motion sensing Cycle storage provided (garage) Surface runoff collected or attached to municipal drainage system Low-risk flood zone (95m elevation on hill) Finishing materials- locally sourced timbers Internal and external recycling bins provided High sound insulation value of straw bale Energy Efficiency User Guide supplied with home Construction contractor must work to Considerate Constructors Standard Security to PAS24-1 Standard and achieved Secured by Design (SbD) award
DRAWBACKS / IMPROVEMENTS Rural location- poor transport links. Ecohomes does not give consideration to use of electric vehicles Rural location on existing field- slight damage to local ecology Consultation must be undertaken with an accredited ecological expert to ensure minimising of ecological damage Consideration can also be given to techniques to enhance local ecological value Building footprint ratio 1:1 (single floor)