.JPG)
Plan for four zero carbon eco towns by 2016 in the UK approved by ministers.
To be located at Rackheath, Norfolk; Whitehill-Bordon, Hants; NW Bicester, Oxon; & Nr St Austell, Cornwall.
The plan includes biomass fuel, solarpanels, water recycling, high building insulation, electric transport.
Eco city in desert - Masdar, Abu Dhabi - complete by 2018 for 30,000 people (ref197).
A zero carbon zero waste traditional walled city is being designed by Foster Architects, supplied by a solar and wind power station and solar operated desalination plant for water supply but with standby connection to external transmission lines and tree plantations for biofuel and waste recycle. Solar mirrors will focus the sun on power generators in the power station.
Features are lower layer, driverless electric cars dialed up by mobile phone; 20 feet above are buildings, shops etc; overhead electric sky rail. Building design is to encourage air flow and shade: awnings with solar panels: canals - cost estimate $22 billion or $500,000 per inhabitant. Houses are being allocated now. See Masdar initiative.
Dongtan, Chongming island, Yangtze, China - by 2010 housing up to 5000 people & by 2050 for 500,000 people design by Arup - 86 sq km site. (ref 197)
Energy sources will be solar cells on grass rooftops, wind turbines, biomass plant using waste from rice production to generate steam/electrical power, and methane gas from digested sewerage and waste materials. Waste is also to be recycled for fertilizers.
Transport will be either electric from the renewable sources or hydrogen. Petrol and diesel cars must remain on the city boundary but hybrid cars will be switched to battery mode when crossing city gates.
Malmo city Sweden sustainable energy project (ref 196) uses heat storage.
Heat storage in aquifer plus heat pump supply 85-90% of heating, other 10-15% comes from solar collectors. These are angled to the sun and vertical in winter. Buildings have 300 mm insulation in walls, 500 mm in roof and 350 mm in the floor, windows U value 1.0 (w/m 2K.) Waste is broken down by anaerobic digester to CO2 and methane, which is used to supplement district gas heating system.
CO2 emissions worldwide
CO2 emissions worldwide (ref 237) are caused by :-
-
Buildings, heating and lighting 21%
-
Industry 33%
-
Transport, cars, lorries, bus, train, boat, aircraft 14%
-
Forestry 14%
-
Agricultural waste 18%
There is much scope for making savings but so far governments have given minimal incentives to do so.
Eco estates and housing - northern (cold) climate version.
Eco houses of the future in cold climates are being developed now.
Eco house features include very good insulation all round, large windows facing southwards to provide passive solar heating (possibly with double glass wall-greenhouse area to trap sun with vents to cool in summer) and a heat pump. Where practical, other features could be included such as wind generator, solar voltaic electrical generation, reimbursed power return to grid, solar water heating, biomass wood or waste heating.
The inside of the BASF house wall has a 'boarding' made of Micropal phase change material which assists in absorbing heat as temperature rises and emits heat as it falls. It is connected to the electric distribution supply for periods when demand exceeds self supply.
Eco estates would have eco houses, provide battery or hydrogen public transport and encourage electric /hybrid cars; fossil fuel being discouraged or disallowed.
Eco house showing most alternatives:-
In restricted areas around the house, eg for commercial buildings, the 'cold pipes' underground could be vertical. Where ground is limited, to prevent the ground slowly freezing as heat is extracted, heat could be pumped back to the ground in summer from solar heating and /or air conditioning, or air heat pumps used. See heat pumps.
Eco house of the future (cold climate.)
The development of most eco houses in cold climates could include electricity generated from Photo Voltaics feeding a heat pump for house heating and hot water. Energy storage can be provided by a diffuser to split water into H2 and O2 which can then combine in a fuel cell to provide power at night or when sun power is low. The heat pump could provide up to 5 times the heat energy of the electrical energy used to drive it.
Algae powered house
'Algae plus' generates biogas for water/space heating and hydrogen for electricity via a fuel cell. Design by Cambridge students.
Algae powered house of the future
Energy collected by panels of photovoltaics and stored hydrogen USA.
The Hopwell project in a house owned by Mike Strizki in New Jersey USA uses electricity generated by solar panels with no connection to the electrical power grid. The excess energy over that required in the summer for all purposes including air conditioning is used to generate hydrogen which is stored to regenerate electricity when solar panels are not operative or partly operative, on cloudy days and winter. The project cost $500,000. Ten 1000 gallon storage tanks for hydrogen are located on a large piece of land (ref 167).
Micro CHP (Combined heat and power) - Biomass or wood chips or gas
CHP systems use heat generated in a boiler to generate electricity (via for example a sterling engine) and the remaining (reject) heat after the process provides local heat. This is an efficient way to generate electricity as the heat after use for generation is not wasted but used. 1kw of electrical power could be generated for 2kw of heat for central heating. The benefit to the consumer will be the regeneration credit from the electricity supplier.
Combination of Heat & Power (CHP) and Heat Pump (HP).
An overall efficiency of up to 150% from burning fuel- to-heat generation can be obtained in a district heating process.
Concrete that absorbs CO2
Novacem has developed a concrete that uses magnesium oxide which with other mineral additives hardens the mix by rapidly absorbing CO2 from the atmosphere.
Concrete manufacture accounts for 5% of manmade CO2, in the course of which the cement is heated to 1600 C, whereas Novacem's production needs half this temperature. A tonne of Novacem produces 200 - 400kg CO2 compared to 700kg for Portland cement. While Portland cement absorbs 100 to 500kg per tonne of CO2 during setting, Novacem absorbs 2.5 times this figure. Another advantage is that Novacem can be recycled with other waste material after a building has been dismantled by mixing with aggregate, glass or plastic. (ST buis 12 5 09.)
Energy performance contracting
Business owners outsource the whole business of improving energy efficiency; thus obtaining new more efficient plant and services without themselves having to find the capital for investment, boilers, lighting etc and they should therefore save on cost. The contractor obtains the business and should make a profit, the environment gets fewer CO2 emissions.
Siemens Buildings Technologies is, by providing this service, generating energy savings of $1 billion in the US, has schemes for 6500 buildings worldwide and claim greenhouse gas reductions of 2.4 million tonnes pa.
Smart metering
Smart meters gives users in-home display of energy used and thus more control of it; and enables remote and thus accurate reading. (ref 216 & 205.)
Smart metering allows excess energy from users (generated by the user from intermittent sources wind, solar etc ) to be fed back to the grid and credited; thus excess intermittent energy is shared not wasted and overall the consumption of electricity (and generation of CO2) would be lower (ref 177).
A further development is a smart grid where load sensing devices could be arranged to reduce consumer load - eg turning down heating slightly - at times of excess load experienced by the national electricity supplier, with 'dynamic pricing' incentives. The timing of battery charging on battery cars of the future could also be adjusted to suit periods of low load demand eg when load falls at night.
