Energy use: sustainable solutions

What should be the overall approach to reducing energy use?

• Adopt the 'Energy Hierarchy', as set out in the Regional Planning Guidance (2002 and revised 2004) which recommends that the following order of priority is pursued in all development schemes:
  • Reduce the need for energy
  • Use energy more efficiently
  • Shift to using renewable energy (including purchase of green power from an accredited scheme)
  • Ensure that any continuing use of fossil fuels is clean and efficient (for heating and co-generation)
• Minimise embodied energy in construction by choice of materials and systems.

How can solar gain be maximised to reduce heating requirements?

• Avoid overshadowing from nearby buildings by allowing adequate spacing and be aware of permanent shading from trees (although they can provide shelter from winds to reduce heat loss).
• Orientate the main building elevations to face south and size the windows in order to provide long periods of sun and daylight.
• Consider the use of roof lights and atriums to bring light and solar heat into the centre of buildings.
• Be aware of the overheating effects of solar gain in summer months and design accordingly.

How can heat loss be reduced?

• Explore the advantages of designs that utilise high thermal mass (see Building Design and Specification).
• Ensure an airtight construction with adequate controlled ventilation.
• Reduce the area of exposed external surface by selection of building type / design.
• Provide substantial layers of insulation and maximum draught proofing.
• Include unheated ‘buffer’ spaces attached to main building areas to store the sun’s heat and reduce exposure to cold (e.g. porches, conservatories and atriums).
• Utilise advanced glazing systems giving preference to low-E (emissivity) glass.
• Consider secondary glazing systems as a simple retrofit measure.

Why should and how can Building Regulations be exceeded?

• Treat UK building regulations as a minimum standard which can be raised by limited extra investment, often giving an effective payback as well as wider environmental benefit.
• Aim for the highest rating by use of a recognised assessment method (see ‘Tools for Assessing Environmental Performance’ in Further Resources and employ it as a positive marketing point for the property.
• Investigate the potential for zero heating (i.e. heating only from solar gain, plus the heat given off by electrical equipment and occupational activity), especially in houses and leisure/commercial buildings - which will normally increase their marketability.

If heating systems are required, what are the most energy efficient solutions?

• Size the system correctly, as oversizing is common bad practice, and use zoning where appropriate.
• Install high efficiency boilers (note: consider condensing systems) with understandable heating controls and high standards of insulation throughout (storage cylinders, pipework etc), and ensure operators are trained in their use.
• Consider wood fuel boilers.
• For larger buildings, consider the potential for connecting to a community district heating or combined heat and power (CHP) scheme, including the option of establishing a new shared scheme in the area.

How can energy use be managed for the benefit of building occupants?

• Reduce the need for hot water as far as possible - install low consumption appliances (e.g. showers).
• Opt for ‘A’ rated energy appliances with sophisticated timers where appropriate.
• Eliminate the need for air conditioning by maximising opportunities for natural ventilation.
• Ensure that heating, lighting and ventilation controls can be easily set to meet the needs of occupants.
• Consider remote rather than central systems where dictated by long pipe runs and low demand.
• Consider installing active solar water systems (see Renewable Energy.)