16469 Low Energy Building Design Sustainability – an overview

1. 16469 Low Energy Building Design Sustainability – an overview Dr Nick Kelly ESRU

2. Origins of Sustainability • Stockholm agreement (1972) addressed environment, economic and social development and outlined 26 principles for sustainable development . • Brundtland Report (1987) defined Sustainability as: • "Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs".

3. UK Implementation • The UK government has published its guiding principles with regards to sustainability • http://www.sustainable-development.gov.uk • Covers much more than just energy and natural environment • economy and employment • social justice • communities • etc.

4. UK Implementation

5. UK Priorities • FOUR key areas: • sustainable consumption and production • climate change and energy • natural resources • sustainable communities • ALL of these areas relate to the built environment

6. Sustainability in Buildings “Sustainable building design should aim to provide a balanced solution, offering optimum working/living conditions, alongside reduced environmental impact, both now and in the future. Taking the complete building lifecycle into consideration, there are many factors involved, from the location of the building, its design, subsequent operation and maintenance, to the construction materials and practices used, and how any future changes of use are addressed.” D. McLean (IET)

7. Production and Consumption • sustainability necessitates controlling energy demand in addition to developing renewable/low carbon energy supplies • the built environment is the largest final energy consumer • in the built environment 40%3 of the energy consumed is used is for space heating with most heating systems running on natural gas • overall energy consumption is on the increase with a 19% rise in the domestic sector and 17% rise in the services sector since 19903 • driven by: • demographics (increasing # of households 18.6M – 24.2M 1971-20054) • comfort expectations (average internal temperatures have risen 5oC since 19705) • lifestyle (multi-source lighting, increasing use of electrical appliances) Sources 1 DUKES 2005, 2 NS Social trends 3 Energy consumption in the UK 4 NS Social trends, 5 domestic energy fact file 2001

8. Climate Change and Energy • the domestic sector alone accounts for 28%1 of final energy consumption and 42 million tonnes of carbon (MtC) per annum2 • UK-wide buildings accounting for over 40% of all UK carbon dioxide emissions, and with as many as 140,000 new homes needed each year it is no surprise that reducing these emissions is currently a key focus • improving energy efficiency has been identified as being the cheapest, cleanest and safest way of doing this • renewables alone DO NOT reduce energy consumption but can reduce electricity taken from the grid and the use of fossil fuels Sources 1 DUKES 2005, 2 NS Social trends 3 Energy consumption in the UK 4 NS Social trends, 5 domestic energy fact file 2001

9. Natural Resource Protection & Environmental Enhancement • In 1998 the construction industry consumed over 420 million tonnes of materials • 83% was primary materials • the construction industry accounted for around 80 million tonnes of waste per year (4 x domestic waste) • the resource efficiency is 63% • the day-to-day operation of buildings also consumes significant quantities of materials inc. treated water • sustainable buildings should use less raw materials in their construction and produce less waste – through the use of re-cycled materials and re-cycling of waste, re-cycled aggregates, insulation materials, etc, use of ‘grey’ water, etc Source: The Construction Industry Mass Balance: resource use, wastes and emissions R A Smith, J R Kersey and P J Griffiths

10. Sustainable Communities • the UK’s sustainable development priorities also include the need for sustainable communities – covering the social aspect of buildings • relevant aspirations are: • environmentally sensitive - providing places for people to live that are considerate of the environment. • well designed and built - featuring a quality built and natural environment. • well connected - with good transport services and communication linking people to jobs, schools, health and other services

11. Legislation • also remember that new legislation is emerging that forces designers to think sustainably: • legislation, specifically related to buildings includes • Home Energy Conservation Act • London Energy Strategy (using planning powers) • Local planning regulations • Energy Performance in Building’s Directive (energy performance and renewables) • New building regulations (energy performance and renewables)

12. Achieving Sustainability • To maximise sustainability in a building design a global strategy is required: energy use occupants resource use transport strategy renewables emissions local community waste and recycling

13. Measuring Sustainability • How can the resulting ‘sustainability be measured? • Single or multiple metrics? • UK government currently has 127 indicator measures and 68 indicators on sustainability • not all relate to buildings

14. Performance Metrics

15. Performance Metrics • GHG emissions • energy consumption • renewable electricity/heat • resource use (water/fuel) • road transport • waste/recycling • air Pollutants • land use • … • community participation • employment/poverty • education

16. Performance Metrics • to judge sustainability need to compare performance against a reference!

17. Comparison • e.g. 1997 regs house vs passivhaus

18. Comparison • e.g. 1997 regs house vs passivhaus