Renewable Energy Options
In an industry serious about climate change, property has turned its attention to renewable energy sources, fuelled new legislation and the Government’s goal of reducing Co2 emissions by 60% by 2050. New planning policy and regulations are now setting minimum requirements for on-site renewable energy and EPCs (Energy Performance Certificates) are being introduced for every building being constructed, refurbished, sold or let.
It can be expensive to implement on-site renewables, particularly in urban city centre locations. The combination of premium land prices, increasing build costs and the cost of the energy sources themselves have to be weighed against rental returns and overall profitability.
New developments can be ‘future proofed’ by improving insulation, using sustainable and low carbon materials, as well as installing solar shading and advanced glazing. Some developers have gone as far as to install ‘green roof’ which means the roof of the building soaks up water rather than it running into the local system.
Some sources available in the UK to generate energy and reduce dependence on fossil fuels, as well as reducing carbon footprint:
Ground source heat pumps utilise energy stored at a constant temperature in the ground. This requires a modest amount of space and is an efficient use of technology. The pumps are a significant investment but are easily integrated with the majority of property heating and cooling systems, operating in a similar way to a household fridge. This technology will be used at Mountgrange’s Caltongate development in Edinburgh, Holes will be bored 50 metres into the ground and water will be fed into a heat pump unit, providing heating and hot water.
A much talked about and popular option is converting wind energy to produce electricity via wind turbines. A strong, steady wind speed is required for the impellers (sails) to drive the turbines. The expense of setting up wind turbines is high but they are very cost effective once in place. Turbines have come under fire by conservationists looking to preserve the aesthetic of our city and landscape. In a city centre location it will be challenging to retain the architectural aesthetics of buildings with wind turbines on roofs. The Torres Building at Scottish Enterprise Park at East Kilbride is currently using wind turbines for power. It is more likely that this technology will be used in housing, business park situations or HQ offices.
Photovolaic (solar power) converts the sun’s light into electricity and operates in even overcast weather. A large proportion of the property’s roof - around 50% - is needed to accommodate the expanse of solar cells required to power a large building or a development. PV cells are expensive but are easy to integrate. They operate best facing south at 30 degrees but work well with solar shading and need to be fully replaced every 25 years. Solar panels can be used to convert the sun energy to heat water and are a less expensive option. Edinburgh City Council’s headquarters and the Scottish Natural Heritage headquarters at Great Glen House in Inverness use solar panels to heat water.
Biomass heating involves burning woodchips or pallets to heat buildings. The cost of installing the system is high however this method uses clean, carbon neutral fuels. The benefit may be lost by traffic delivering the fuel and the storage area required for the wood but grants may be available to make this option more attractive. It is dependent on the boiler being accessible. Queen Margaret College at Newcraighall uses biomass heating.
Rainwater harvesting recycles water, making a significant impact at a modest cost. It is used to provide water for toilets etc. Rainwater is gathered and filtered into a storage tank and is then pumped through the system, topped up by mains water supply. Several new developments are using rainwater harvesting.
There is a number of alternative sustainable technologies including geothermal heat, ground cooling air systems, solar air collectors, all with very limited experience within the UK.
In selecting renewable energy sources we must also look at the environmental systems and in particular both client and end user issues such as capital cost, design criteria, adaptability, comfort/controllability and ease of maintenance.
Everyone should be looking at the positive energy changes they can make now within their property. The issue affects tenants, owners, investors and developers alike. The options should be carefully assessed and expert advice sought, particularly for new buildings. For these, consideration should be given throughout the project, from the selection of design team to the site's natural ventilation, orientation for solar shading, availability of ground source water supplies and exposure to wind.
For further information peter.i'anson@ryden.co.uk
|