District Heating: It’s Becoming Centrally Important – Marcus Eves, Darren Evans Assessments

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There is an old saying that there is nothing new under the sun and district heating certainly isn’t a new idea. The concept, also known as community heating, has been around for decades and has been implemented successfully throughout the world, particularly in urban environments and other areas of high building density.

District heating is a straightforward idea which can bring fantastic efficiencies and while its uptake in the UK has been relatively slow, the agenda to combat fuel poverty may mean this is about to change. Simply put, heat and hot water are supplied to a number of buildings from a central energy source via a network of insulated pipes. Heat exchangers in each of the buildings deliver the heat to them, removing the need for individual boilers or other heat source, with the network acting as a normal wet system.

The drivers for district heating in the UK are also well established. Regional and national targets for energy saving and carbon reductions are forcing councils to implement as many sustainable strategies as they can think of. You will not read a Core Strategy or Local Development Plan without coming across the phrases ‘sustainable communities’ or ‘district heating.’

Many UK local authorities are taking a keen interest in district heating following the success that has been seen in some nearby European cities. Copenhagen for one has had a network since the 1970s, and today this delivers 98% of the city’s heating needs. London and the rest of the UK have come a little late to the party however and will view this figure as an impossible goal. There are currently not enough heat networks so retrofitting to meet demand is a certain challenge on the infrastructure.

Local and Regional policies are however pushing for the need to future proof. The beauty of heat networks is that once an insulated network of pipes is laid, what is connected at the end to produce the heat can change and adapt as the environment around it changes or a technological development is achieved. This could involve replacing fossil fuel plant with renewables such as biomass or tapping into waste energy, such as the scheme currently being considered to utilise the 25°C air which is vented all year round from the London Underground.

If you are building a major development within the confinements of the London Plan (the GLA’s overall strategic plan) it is mandatory to consider decentralised generation of heat and power. The expectation is, where appropriate, that the developer’s proposals should seek the follow a hierarchy as follows: 1. connecting to an existing heating or cooling network, 2: implementing a site-wide CHP network, 3. installing a communal heating and cooling network. Any system should be future-proofed and designed to connect to a district network if one becomes available.

When designing the layout of the site, thought should be given to its density and optimising installation of a system. This will include understanding the energy demand of the site, identifying locations suitable for heating plant and associated hot water storage as well as internal layouts for the risers required to move the water around the building.

There are a number or online tools which can help developers maximise the potential savings available for implementing community and district heating. Arup for example has developed a Carbon Calculation Tool which allows developers to estimate CO2 savings for new and existing district heating schemes with different sources of heating. Another useful resource is the London Heat Map which has been developed as an interactive map which identifies where existing heat networks are located and areas outlined as having potential for decentralised energy.

Where a site has been identified as suitable for a community heating system, consideration must be given to the use of Combined Heat and Power. This is a well-known approach to simultaneously producing electricity and heat onsite increasing energy security. Further to simple environmental benefits, the introduction of CHP can bring both social and economic benefits in the form of low cost electricity and affordable warmth, lower life cycle costs and lower management/maintenance costs. The system must be sized adequately in order to ensure a constant operation which will maximize the potential savings.

With stricter regulations on installation, regulation, maintenance and control the installation of a district or community scheme enables the efficient transportation and use of heat for a wide variety of users. There are unrivalled opportunities to allow a broad range of energy generation technologies to work together to meet demand for heat enabling fuel flexibility. Although capital cost can be high, the whole life cost benefit from infrastructure which can be expected to last much longer provides a means of securing significant reduction in CO2 emissions through the optimisation of heat supply.

The opportunity for improved local fuel security via district heating must be seen as key to helping to provide a long term method of tackling fuel poverty.

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Reasons To Buy Into Breeam – Michael Brogden, Director, Darren Evans Assessments

BREEAM in-use Certificates world map September2012

BREEAM was developed 25 years ago by the Building Research Establishment as a comprehensive assessment tool for demonstrating a building’s sustainability against a wide range of criteria. During its lifetime it has grown to become an internationally respected system of established benchmarks and industry recognised measures for evaluating the specification, design, construction and use of buildings. However, what are the key reasons that you might consider implementing BREEAM on their project?

If you are an architect or a specifier, one of the best reasons to choose BREEAM is that the broad range of environmental criteria which it covers enables you to demonstrate your firm’s variety of skills in delivering environmentally friendly as well as energy efficient buildings. The process of achieving the credits required within each of the relevant categories within BREEAM encourages designers and contractors to seek innovative ways of delivering projects and to consider environmental aspects at a much earlier point in a project than might normally be the case.

The certification demonstrates that reducing environmental impact is high on the agenda of the whole product team, and that the design team has managed to deliver on that agenda. Buildings certified under BREEAM will have lower running costs, lower water and energy consumption and less waste, and often incorporate passive design principles, renewable energy and responsibly sourced building products with lower embodied energy. Therefore, it is a sign that a more thoughtful approach has been taken throughout the project.

For building owners BREEAM is the recognised badge that shows they have maximised the sustainability potential of their building. In addition, the rigorous way that BREEAM rated projects are audited and run provides a credibility which gives confidence in the ratings which are produced at the end of the process, whether the building is Very Good, Excellent or Outstanding. This plus the wide and growing awareness of BREEAM across all sectors of the industry enables buildings to be differentiated in the marketplace and command a higher degree of desirability. This is crucial in the commercial sector for example where BREEAM rated buildings are typically rented faster to tenants.

For contractors, BREEAM enables firms to demonstrate best practice when it comes to delivering sustainable construction which for example diverts as much waste from landfill as possible and reuses materials. In addition, certification shows that they are able to reduce ecological damage caused by construction, and are focused on increasing ecological value on sites where possible. Successful BREEAM projects mitigate pollution incidents, minimise impact on neighbours and increase biodiversity, as well as use of local suppliers. Achieving all of these benefits is assisted by the fact that the process of undergoing BREEAM helps improve monitoring of these factors.

Some other compelling reasons to adopt BREEAM:

  • The assessment tool tends to encourage buildings to be designed for longevity and future adaptation, making them more resilient
  • Certification shows that the build reduces ecological damage from construction and adds value to the local community
  • BREEAM helps to create buildings that are fit for purpose for the client via the consultation approach which is inherent to achieving the certification
  • BREEAM buildings provide a healthier environment for users with increased holistic benefits such as natural light and ventilation
  • BREEAM demonstrates that reducing environmental impact is top of the agenda for building owners, architects, contractors, developers and end users.

As it celebrates its 25th birthday, BREEAM is without doubt a success story for the construction industry, helping raise the bar for sustainability in the UK and internationally with a robust assessment system which adds tangible value. With over 425,000 buildings having been assessed so far, that means a lot of projects which are offering healthier, better environments for employees plus a good image for construction’s ability to achieve measurable sustainability improvements.

Water efficiency: meet legislation, reduce your bills

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Did you know that, in the UK, we use 55% more water than we did 25 years ago? As the effects of climate change increase, it becomes ever more important to use water wisely, and to build homes that conserve water as much as possible.

According to government legislation, all new dwellings must comply with Part G regulations, i.e. that no more than 125 litres of water should be used per person, per day. There are numerous ways to achieve this, including fitting a wide range of water-efficient fixtures around the property. In our extensive assessment experience, the most effective include:

– Newer acrylic baths with a slightly smaller capacity: the water stays hotter for longer, and less water is needed to fill it.

– Water-efficient shower heads and lower-flow taps: the amount of water released while the tap or shower is running is reduced significantly.

– Grey water recycling units: water from showers, basins and baths can be reused for flushing toilets. Since it is estimated that a third of all water usage comes from personal washing (showers, baths and basins; see http://www.waterwise.org.uk), and an additional third from flushing the toilet, this can represent a huge saving.

– Modern WC units, especially dual-flush toilets: older toilets can use up to 13 litres of water for a single flush, whereas a modern unit uses only around 6 litres to flush. Dual-flush units use only between 4 and 6 litres per flush.

– Flow-limiters for water pipes: these are installed within the pipe itself, and reduce the flow of water from the tap or shower.

How can we help?

Our team of assessors is fully qualified to advise on water efficiency at any stage of your build process: we can suggest measures to include at design stage, ensuring your property plan will meet Part G regulations, or view the property after completion to calculate current water efficiency and suggest improvements. We have experience with all types of water-efficiency fittings, and will work hard to make your build as cost-efficient as possible.

Water usage at home

There are many simple ways you can reduce the amount of water you use in the home. Try some of the following and watch your water bill decrease!

– Turn off the tap when brushing your teeth. Leaving a tap running for five minutes uses 18 250 litres of water a year, but using a tumbler for rinsing instead can save 16 425 litres per person, per year.

– Take a shower instead of a bath – this can reduce your water usage by up to 40% – and try reducing the time you spend in the shower by one minute. This will decrease your water and heating bills simultaneously.

– Put the plug in when washing hands or shaving. It can reduce water usage by half.
Insulate pipes and know where your stop taps are, to reduce the amount of wasted water and damage in case of a burst pipe.

– Don’t use the toilet as a waste bin: putting items like makeup wipes, dead spiders and the contents of your hairbrush into the WC can add up to many wasted flushes a day.

If you’d like any more information on water efficiency, or would like our assessors to visit your property, contact us now on 01454 317940. We’d love to hear from you.

Or for more general information and advice, try these online sources:

http://www.water-efficiencylabel.org.uk/bewaterwise.asp

http://www.waterwise.org.uk/pages/at-home.html

http://www.energysavingtrust.org.uk