Glossary of EcoTerms

Biomass Boilers

These are boilers that burn organic matter of recent origin, rather than fossil fuels which have taken millions of years to form. They commonly burn wood in the form of logs, chips or pellets, but can also use fast growing crops such as willow or miscanthus as fuel. This is a low carbon technology, because the wood when it is growing absorbs carbon dioxide and when it is burned it releases this carbon dioxide again. So long as more trees are planted this process is sustainable.

• Wood Pellet Boilers are a highly efficient type of boiler. The wood pellets are made from sawdust which is heated and compressed into pellets. This is then stored in a hopper before being fed into the boiler.

BREEAM

Stands for ‘Building Research Establishment Environmental Assessment Method’; a method of rating how sustainable (mainly)a commercial property. Newly introduced the top rating is ‘Outstanding’. The method considers a wide range of locational and property features to produce a ‘score’ for the property which is then equated to a rating. Generally regarded to be the most widely accepted method of rating commercial property in the UK.

Brise Soleil

This is a permanent sun shading device attached to a building. It often takes the form of louvers on facades with a large amount of glass. These prevent the high angle summer sun from falling on the building but allow the low-angle winter sun which can help to heat the building.

Carbon Footprint

The total amount of carbon dioxide attributable to the actions of an energy user (mainly through their energy use) over a period of one year.

CEA

Commercial Energy Assessor

CHP

Combined Heat and Power is the simultaneous generation of usable heat and power (usually electricity) in a single process. In its simplest form, it employs a gas turbine, an engine or a steam turbine to drive an alternator and the resulting electricity can be used either wholly or partially on-site. The heat produced can be used to raise steam for a number of industrial processes or to provide hot water for space heating.

This is a highly efficient process where there is a need for both heat and power.

More info: www.chpa.co.uk

CLG

Department for Communities and Local Government

CSR

Corporate Social Responsibility

DEC

Display Energy Certificate

EMP

Environmental Management Plan

Energy Monitoring Systems

This is a way of measuring energy use in a building to get more detail than a utility bill provides.

Measurements of electricity, water and gas can be provided at regular intervals, often half hourly. These can then be used to look for energy saving opportunities.

More info: Advanced Metering for SME's a free publication from the Carbon Trust www.carbontrust.co.uk

EPBD

The EU's Energy Performance for Buildings Directive, which all member states must implement by January 2009.

EPC's or Energy Performance Certificates

This is a certificate giving the energy performance of a building on a scale of A-G. It is required for housing and on commercial buildings of floor area > 500m² at point of sale or rent and also for new buildings.

FSC Timber

This stands for Forest Stewardship Council and is a certification scheme for timber. FSC certified forests are managed to ensure long term timber supplies while protecting the environment and the lives of forest-dependent peoples.

(There are other timber certification schemes such as PEFC, MTCC, CSA and SFI but these do not consider the lives of the local people.)

FSC certified timber is widely available in timber merchants such as Travis Perkins and Jewsons.

Green Leases

This is a way to incorporate environmental best practice into commercial tenant lease agreements. The legal implications of this are still being explored.

Green Roof

A roof of a building that is partially or completely covered with vegetation and soil, or a growing medium, planted over a waterproofing membrane. There are 2 main types classified according to how much maintenance is required:

Intensive Green Roof

These are the traditional ' roof gardens', which require a reasonable depth of soil to grow large plants or conventional lawns. They are labour-intensive, requiring irrigation, feeding and other maintenance.

Extensive Green Roof

These are designed to be virtually self-sustaining and should require only a minimum of maintenance, perhaps a once-yearly weeding or an application of slow-release fertiliser to boost growth.

They are composed of lightweight layers of free-draining material that support low-growing, tough drought-resistant vegetation such as Sedum. Extensive green roofs can be designed into new buildings, or 'retro-fitted' onto existing buildings.

More info: www.livingroofs.org

Grey Water

This is water from domestic processes such as dishwashing, laundry and bathing.

(Waste water from the toilet is called blackwater)

www.environment-agency.gov.uk/subjects/waterres

Ground Source Heat Pumps

A means of tapping into the natural heat generated from the earth based on the constant temperatures below ground which can be used as a heating source in the winter and a means of cooling in the summer.

Heat Pumps

These work rather like a fridge in reverse. A small temperature difference between a building and the surrounding ground, air or water can be used to heat or cool the building. A liquid which boils at a low temperature is passed through pipes. The warmer temperature causes the liquid to change to a gas. This is then compressed by the pump and condenses, and at this point it gives out heat. This is useful heat which can be used to heat a building. There are 3 main types of heat pump:

• Ground Source Heat Pump - this takes advantage of the constant temperature of 8-12ºC of the ground at a depth of 1 metre or more. Pipes are laid and can run vertically or horizontally in the ground. They can convert this small temperature difference from the air to usable heat. The heat produced can be 3 or 4 times the amount of energy required to run the pump.
• Water Source Heat Pump - this works in a similar way but pipes run in a nearby lake or pond.
• Air Source Heat Pump - these use the external air as their heat source and can be seen widely attached to the outside of buildings looking like a fan inside a white box. They take the heat from the air and transfer it by means of fans to the building.

Ground Source Heat Pumps are the most efficient but also the most expensive to install.

More info: www.heatpumps.org.uk

Heat Recovery Ventilation

This is a more efficient system of ventilation than straightforward mechanical ventilation as it reclaims the energy from the exhaust air and transfers it to the incoming fresh air. This can be done by transferring the heat to a series of metal plates and then on to the incoming air. These systems can recover about 10 times as much energy as they require to run, and up to 95% of the heat can be recovered in this way.

High Efficiency Gas Condensing Boilers

These boilers extract heat from the exhaust gases that would otherwise escape through the flue - turning water vapour from the gas back into liquid water or condensate. Replacing your old boiler with a new condensing boiler can save you around a third on your heating bills straight away.

HVAC

Heating Ventilating Air Conditioning

Hydropower

This is power created by moving water. Movement of water in rivers can be used or wave or tidal power in the sea. Hydropower supplies 19% of the world's electricity.

Intelligent Lighting

This type of lighting has automated or mechanical abilities beyond those of traditional, stationary illumination. Sophisticated controls can be fitted to regulate levels of light for different scenarios. It can be used for energy saving.

Lightweight Buildings

These are buildings with low thermal mass (see definition). They heat up quickly when heat is added and cool down quickly when the heat is removed. Timber framed buildings are a typical form of lightweight building. This can be useful for a building that is intermittently occupied.

Low e Triple Glazed Argon filled Windows

This is a high specification glass. Low-e or low emissivity glass has a metal coating which increases the energy efficiency of windows by reducing the transfer of heat or cold through glass. That means in the winter a house stays warmer, and in the summer it stays cooler. Argon can be used instead of air in the spaces between the panes of glass. Argon is better insulator than air. Triple glazing is better than double glazing at conserving heat and at sound proofing.

Microgeneration

This is the generation of zero or low-carbon heat and power by individuals, small businesses and communities to meet their own needs. E.g. a wind turbine, solar panel, solar pv, chp for an individual building, etc.

OR

Operational Rating

Part L of the Building Regulations

This is the section of the Building Regulations that governs the conservation of heat and power in homes, offices and other buildings.

Passive ventilation

This is ventilation that uses no mechanical energy to run. In its simplest form openable windows are a form of passive ventilation. 'Passive stack ventilation' operates by means of wind induced pressure differences. An outlet duct is fixed on the roof and inlets are positioned lower down in the building. Pressure differences cause a movement of air upwards and out, drawing fresh air in through the building. On very still days some assistance may be needed to these types of passive systems.

Passivhaus

A standard of building for residential as well as commercial buildings where little or no heating system is required. The building shell is extremely airtight and well insulated with minimal thermal bridges. A high performance ventilation system recovers up to 95% of the heat produced within the building from people, equipment, cooking etc and uses transfers that heat to fresh, filtered incoming air.

More info:

www.passiv.de

www.passivhaus.org.uk

Rainwater Harvesting Systems

Rainwater run-off from a building is filtered and collected in a large tank usually below ground or at ground level. This is then used for non-potable uses such as WC flushing and washing machines.

More info: www.ukrha.org

RR

Recommendation Report

SBEM

Simplified Building Energy Model

Solar Water Heating

A panel rather like a radiator, often placed on the roof, absorbs heat from the sun that is used to heat water. This should not be confused with Solar Photovoltaic which is also a panel often placed on the roof but which produces electricity by means of photoelectric cells.

SUDS or Sustainable Urban Drainage

This is an alternative to conventional drainage which aims to reduce the rate of rainwater run-off and thus the risk of flooding particularly in built up areas. It also reduces the pollution of watercourses as the water is filtered by the different layers before running into watercourses

A variety of techniques are used including dry ditches (swales), perforated pipes set in the ground, attenuation ponds, reed beds, Permeable paving and 'green roofs' are also useful.

More info: www.ciria.org/suds

Thermal Break Elements

Thermal breaks in a building are areas of thermal weakness where heat can pass through the structure more easily e.g. steel lintels, hold down bolts etc. There is a whole new range of materials being developed to overcome these problems including a fiberglass material to replace reinforcing bar, and more sophisticated hold down bolts to minimize heat transfer out of the building.

Thermal Mass

This is the capacity of a material to store heat.

A building with high thermal mass will warm up slowly but will retain its heat or cool for longer.

Materials of high thermal mass are dense with fairly low thermal conductivity such as concrete, stone, brick, water and earth.

U-value

A measure of the rate of flow of heat through one square metre of a material for every degree temperature difference between one side and the other. Some typical U-values are given below:

	U-value (W/m2K)
Single glazed timber window	4.8
Standard double glazed window	2.2
High performance triple glazed argon filled timber window	0.7

Low U-values are desirable for energy efficiency.

Wind Turbines for Buildings

Wind turbines can be used to make electricity. These range from small roof mounted turbines of 0.5 to 2.5 kW to the large mast mounted turbines of 1-2MW used for wind farms and increasingly appearing singly on industrial sites. Businesses generally chose a smaller machine producing less than 1MW.

Turbines can be either stand alone or grid connected. Grid connected is the most useful as this can export electricity when it is not required by the building.

A 6kW turbine would typically cost £20,000 to instal excluding groundworks and could be expected to produce 6-12,000kWh on a suitable site.

The output of a turbine is related to the square of the diameter of the blades. So a 2 metre diameter turbine generates four times as much power as a one metre turbine.

The turbine output is related to the cube of the wind speed. So a turbine that generates 1kW at wind speed of 12.5metres/second will only generate 125W at half this wind speed.