Factory Manufacture: The Route to Reliable Renewables?

Factory Manufacture: The Route to Reliable Renewables?

Release of the new Building Regulations scheduled for April 2010 may be delayed in light of the looming general election, but they’ll arrive soon enough!  And with CSH level 4 becoming mandatory for affordable and social housing, renewable energy systems are a real necessity.  But it’s not quite as simple as slapping a few solar panels on the roof; Offsite factory manufactured systems and careful integration offer the best route to achieving substantial, sustainable improvements, argues Martin Goss, MD of Mtech Consult.

The new Building Regulations Part F (Ventilation) and Part L (Conservation of Fuel and Power) will have a significant impact on the construction of new social housing stock, demanding consideration of complex issues such as the recovery of energy from ventilation air; requiring integration of energy efficient and environmentally sustainable ‘living’ systems (grey water recycling, high performance insulations and so) with technologies to generate heat and power in-situ from renewable sources.

Some renewable energy systems are more familiar than others: solar panels for water heating and photovoltaics or wind turbines for electricity supply are reasonably familiar and well accepted; ground and air source heat pumps, waste and grey water management systems and green boilers using biomass or biodiesel fuels, all need to be considered and used where appropriate in a mix to achieve maximum benefit.

On-site integration and installation of many, if not all, of these renewable energy systems involves relatively complex technologies and skills, some of them new to the construction industry.  As the solutions become ever more complex and sophisticated, driven in part by the need to reduce their capital cost, they become increasingly difficult to install and commission on-site.  

But the Offsite construction industry, with its emphasis on forward planning and new product development, is already offering viable solutions.

So, what’s Available Now?

Some Registered Social Landlords (RSLs) are proactively developing procurement chains and standard house designs to meet CSH level 4 and above.  To achieve this, they are incorporating alternative sources of energy (renewables) into the building design and construction.

The most commonly used technologies are solar thermal and photovoltaic (PV) cells on the roof; PVs are set to become more popular as the new feed-in electricity tariffs make the period of ROI much shorter and offer possible revenue generation for RSLs.  But why carry out such detailed and complex assembly operations at roof level, exposed to the elements, when pre-installed systems are available?  A clean, protected manufacturing facility and rigorous inspection/testing regimes in a controlled environment ensures the cells are accurately installed and commissioned, saving time and money.

One tried and tested Offsite solution is the AluPlusSolar system from Kalzip.  Using flexible PV laminates permanently attached to aluminium standing seam sheets, the system is suitable for a wide variety of installations and allows for individually designed roof elements with straight, convex or concave shapes.  The solar cells are in-plane with the roof surface and the PV laminates can blend unobtrusively into the roof profile or become a design feature.

Other renewable energy options for social housing developments include combined heat and power plants or biomass systems such as the Armstrong biomass boiler plant which is delivered to site as a completely factory finished unit, pre-tested and commissioned, easy to install and ready to use.  There are innovative ground source heat pumps with ground loops embedded in factory finished foundation systems; complete rainwater harvesting systems pre-installed in modular housing; the variety and availability of systems is developing rapidly.
Demonstrating how effective a combination of technologies can be, RCK architects of London is employing MMC and solar thermal arrays coupled with a mini district heating system to achieve CSH Level 4 at a 14 house development in Preston for the Community Gateway Association.

Repeatable, Reliable Renewables!

The pent-up demand for affordable housing, a recession-hit UK construction industry with less capacity and a reduced skills base, and increasingly onerous environmental requirements, mean that we need rapid yet innovative, robust and economically viable build techniques.   

But as we chase ever more stringent targets for carbon reduction, the solutions are almost certainly going to require evermore complexity.  Renewable energy technology can involve sophisticated installation and commissioning... getting that right and controlling the cost when it’s carried out on-site is becoming increasingly difficult.   As this type of work is obviously better suited to a factory environment, then Offsite assembly and integration ought to be the answer. 

Many RSLs and their developers / contractors are finding that engaging Offsite expertise, such as Mtech Consult,  early in the process ensures proper, planned integration of Offsite products and systems and delivers the most benefit; not least because the optimum use of Offsite systems provides cost certainty and assured product performance, time after time... it’s totally repeatable... and if the social housing sector is to meet its obligations for incorporating renewables, that’s exactly what it needs.