Sustainable Energy Use & Generation-High-Rise Dwellings

1. Sustainable Energy Use & Generation-High-Rise Dwellings • John Currell - Housing Asset & Sustainability Manager - at Thornsdale 11th March 2008

2. What does Sustainable Development mean? • Brundlandt Report ‘Our Common Future’ (1987) came up with a definition: • ‘development that meets the needs of the present without compromising the ability of future generations to meet their own needs’

3. Can reduce human impact on the environment Helps conserve scarce resources for future generations May help limit the impact of climate change Potential to help reduce our own costs (e.g of heating our homes) Potential to reduce our increasing dependency on imported resources (e.g natural gas) Some reasons for behaving more sustainably

4. Current Policies • Current R & M Sustainability Policy set out in Housings’ Sustainable Building Guidance • Approved by council committee September 2006 & supported by Energy Saving Trust • Aims to support corporate sustainability policies

5. Will need to be issued on all new tenancies from Oct 2008 Includes information on estimated energy use and associated carbon emissions Also recommends measures that could improve energy rating Energy Performance Certificates(EPCs)

6. Energy Use Reductions -What has been achieved so far ? • NHER approved Energy database set up for council managed housing stock in 2003 • In April 2004 the estimated annual carbon emissions from tenanted dwellings was 57,493 tonnes • By January 2008 this has been lowered to 48,456 tonnes, a reduction of 15%

7. Energy Use Reduction Benefits and energy price movements • This energy requirement reduction has improved underlying affordability of energy for tenants, for example by reducing the amounts of energy required for adequate heating • But - improvement undermined by price increases made by utility companies • Most forecasts predict further rises in world energy prices in the medium term due to increased worldwide energy demand and likely limits on supply due to declining known reserves of oil and natural gas

8. Energy Saving Trust states that existing High Rise construction may exhibit any of the following characteristics: Poor thermal performance Out of date and inefficient community heating networks with inadequate controls in dwellings Poor extract ventilation and condensation/mould growth Flat Roofs that are poorly insulated and temporarily patch repaired Concrete or brick spalling Single glazed windows that leak or are draughty Excessive heat loss through very large windows giving onto balconies Thermal bridging from outside to inside due to continuous floor/wall slabs Nationally recognised High-Rise construction characteristics

9. Best opportunity occurs when refurbishment works take place Example: if extensive repairs required to the exterior in any case, it may make external insulation, or cavity wall insulation, where appropriate, much more cost effective Combining measures & programmes will often result in reduced costs and more efficient installation procedures Primary Objective should be to maximise insulation of the building fabric wherever possible Thereafter - most effective reductions derived by improvements to heating systems & controls such as programmable room thermostats Other considerations - controlled ventilation to minimise the causes of condensation Consider scope for introducing low or zero carbon energy sources Opportunities for improving energy performance

10. Low or Zero Carbon (LZC) energy options • Low or Zero carbon energy is term given to renewable energy sources and also to those which emit significantly less carbon in providing heating or power • Often grants can be obtained for part-funding of the installation

11. WALL INSULATION External insulation Internal lining Cavity fill Roof Insulation Improvements Improvements to Windows and doors Space Heating & Hot Water System Improvements All above reduce condensation risk but effective ventilation also required Energy Efficiency Measures Options

12. Opportunities to implement energy efficiency measures

13. Low or Zero Carbon (LZC) Energy Types - Overview

14. Photovoltaic (PV) power • Generates electricity from sunlight • 3 types of solar cells: monocrystalline, polycrystalline & thin film • Can be roof mounted on frame or integrated into building fabric (e.g thin film on canopies) • Electricity generated can be used in the building or sold to the grid • Low maintenance, long-life, no noise issues

15. Combined Heat & Power (CHP) • CHP is the local simultaneous generation of electricity and heat • CHP most appropriate on sites that have a year-round demand for heat or community heating networks • Most common fuel is natural gas, however Biomass can be used • Can be installed in community heating schemes to run as the ‘lead’ boiler. Sizing correctly is important. • Possible to ‘sell’ electricity generated to dwellings, but regulatory obstacles to this (i.e utility company/billing etc) • Alternative is to sell excess electricity back to the grid.

16. CHP - Biomass • CHP system with all potentials of the above, but is ‘carbon neutral’ • Typically wood chips or pellets • Boiler house size - larger than for natural gas due to fuel storage need & access for deliveries • Can produce particles that need filtering by the flue • Can also have gas fired boilers on same site for peak demand or as back up

17. Ground Source Heat Pumps • Utilise the solar heat absorbed by the ground • Refrigerant pumped round a ground loop or borehole(s). Suitable for properties with undeveloped land around them • Input energy is electricity, but up to 4 times energy input is returned as heat. Can utilise locally generated electricity as input fuel • Initial capital costs relatively high due to groundworks but boreholes have very long-life 50 yrs + and little maintenance required generally on the system • Amount of energy available depends on borehole depth and undeveloped land area available. Low output temperature means need boosting for hot water needs. • One of the most cost effective ways of reducing carbon emissions : £119 per tonne according to DTI Low Carbon Building Programme Guidance

18. Wind Power • Wind power can be used to generate electricity for use in buildings, including heating water • Average wind speeds min of 6m/s typically required • On high rise would need to be roof mounted - potential structural , vibration & noise implications (PP required) • Glastonbury House in Westminster gained Permission for a vertical axis wind rotor (VAWT), which have low noise output and start up at low wind speeds

19. General things we can all do • Avoid leaving appliances on ‘standby’ • Install low-energy, long-life lightbulbs • Buy ‘A+’ Rated appliances • Avoid paying for gas/electricity on ‘pre-payment’ meters wherever possible • Consider paying for gas & electricity together and by direct debit • Compare tariffs online e.g theenergyshop.com