The Greenhouse development is using smart and sustainable technology to produce enough energy to fuel the entire site.
- The challenges of refurbishing ‘dustbin’
- Remote-controlled robot demolition
- From development to community
- Using TVs to track bills
- Learning from one development to the next
Energy supply is big news at the moment: politicians are endlessly debating the relative merits of shale gas, nuclear power, offshore wind, solar thermal technology and other green energy sources.
But they have yet to agree on a sustainable energy source that will keep the planet powered in 100 or even 50 years’ time.
These debates directly affect clients, contractors and consumers who finance, build and live in housing all across the country.
For contractors, balancing affordability with sustainability can be a challenge, as can planning for future government changes to legislation while also creating appealing environments for people to live in.
One housing development that is attempting to balance several of these factors is Greenhouse in Leeds. Completed and unveiled in 2010, this 172-home development uses technology to ensure it is entirely self-sufficient when it comes to energy.
The challenges of refurbishing ‘dustbin’
Work to turn a 1930s disused workers’ hostel, previously dubbed ‘the dustbin’, into a sustainable housing development began in 2008, having been initially conceived in 2005.
“Sustainability is becoming more important to people buying homes as fuel prices rise,” says Chris Thompson, founder of the sustainable property developer responsible for The Greenhouse, Citu.
“People are becoming more aware of the benefits of buying or renting more efficient buildings.”
“The technology used allowed us to produce enough energy to make it entirely self-sufficient, while the layout and detail are just some of the ways we’ve been able transform the site into a community”
Chris Thompson, Citu
The company purchased Shaftesbury House, which had fallen into disrepair, in 2008, and began construction work the same year.
Remote-controlled robot demolition
Before work could begin on the extensive renovation of the building’s shell, the main contractor Clegg Construction had to demolish four small inner courtyards that made up part of the original structure.
This included craning a JCB over the existing structure and using remote-controlled robots to take down some edges of the cruciform.
This left the outer core of accommodation stripped back and ready for its refurbishment.
“Residents can track their energy use in real time via IPTV systems, which allow them to see how much energy and carbon is being used”
Chris Thompson, Citu
“With Greenhouse we set out to prove the model,” Mr Thompson says. “Despite the recession, the green agenda was still a priority and we wanted to create a development which had energy-efficiency at its very core, not just as an afterthought.
“The idea was to create a development that was truly sustainable – renovating a disused building, achieving high levels of energy-efficiency and breathing new life into the local area to encourage a sense of community.”
From development to community
Sustainability was clearly a central theme for the £27m project, but not just for the building and its construction but for the residents, too.
“The technology used in Greenhouse allowed us to produce enough energy to make it entirely self-sufficient, while the design layout and attention to detail, such as the residents’ free-to-use gym, vintage bicycle club and onsite deli, are just some of the ways we’ve been able transform the site from property development into a community,” Mr Thompson says.
Aside from the one, two and three-bedroomed apartments, the development also includes 10 creative work spaces and an onsite deli.
The project team installed a variety of technologies and techniques across the development to capture and share energy.
The green technologies used include:
- Two medium-scale wind turbines on the roof to provide a constant supply of energy.
- Solar panels to heat water, circulating it through the building efficiently at peak and off-peak times.
- As the sun tracks around the perimeter, excess heat can be rejected from one apartment and picked up by another.
- The building has excellent insulation and each apartment has a central fan designed to provide ventilation.
- An 80 m-deep borehole provides a constant source of heat from water stored underground.
- Heat machine pumps generate heating and hot water and produce a by-product of air cooling to every home.
- Excess greywater from basins and showers is collected in storage tanks, filtered and then recycled to be used to flush toilets.
“Greenhouse helps its residents save energy and reduce carbon emissions by increasing the energy-efficiency of the buildings and then incorporating various renewable technologies,” Mr Thompson says.
Using TVs to track bills
Data for the first two operational years of the building show the effect using the sustainable technologies is having on the energy consumption of the building.
Figures show that in two years the solar thermal technologies at Greenhouse have generated over 80,000 kWh – this equates to energy capable of heating 54,000 showers or 74 showers a day.
The average Greenhouse home will also save one tonne of CO2 per year, as well as 25,000 litres of water, and residents can benefit from a 48 per cent reduction in typical energy bills as a result.
“It’s a bit like asking why certain parts are chosen to build a car – it depends what you’re trying to do with something”
Chris Thompson, Citu
“Residents can track their energy use in real time via IPTV systems, which allow them to see how much energy and carbon is being used,” Mr Thompson says. “They can also pay their utility bills via their remote control.”
When considering the specific technologies used and the effect they have had on the development, Mr Thompson also emphasises the importance of considering how all the systems work together, rather than just as standalone green technologies.
“We chose these technologies to ensure the building was as efficient as possible and used renewable energy where possible,” he says.
“When Greenhouse was being planned, the products were not as plentiful as they are today, so we had to take our time to find the right suppliers.
“Although the technologies were chosen from a holistic perspective, they also complement each other well.
“It’s a bit like asking why certain parts are chosen to build a car – it depends what you’re trying to do with something, and that determines what parts are used.”
Learning from one development to the next
The practicalities of the site played a role in deciding which systems to use on the project. “Deep ground-source boreholes were required because the plot size wasn’t large enough for surface-based ground-source,” Mr Thompson says.
“Hot water PV was used instead of solar because there were greater efficiencies to be gained from a district hot water system as opposed to PV.”
“We chose these technologies to ensure the building was as efficient as possible and used renewal energy where possible.”
Chris Thompson, Citu
The team also decided to use heating and cooling exchange because it was able to feed into the hot water system and link each apartment.
“A normal air conditioning system would just use energy to expel the heat into the atmosphere,” Mr Thompson explains.
“The heat exchange at Greenhouse first shares excess heat with other apartments that require it, such as the north-facing apartments, and once that demand is satisfied, it is used for heating the hot water.”
As the development has now been operational for nearly four years, the team at Citu use the data and information they gather from projects such as Greenhouse to inform future building projects.
“We learn a lot from each of our developments and we continue to improve and innovate within our speciality of sustainable urban regeneration,” he says.
“Our belief – that everyone should have the choice of living a more sustainable lifestyle without compromising on design – drives how we shape our developments.”