The Client

NAMHA, Northumberland Aged Mineworkers Homes Association (NAMHA) is a registered charity. Northumberland was one of the largest mining communities in Europe. When the mines closed NAMHA was established in order to provide purpose built bungalows for the retired miners and miners’ widows to reside in. NAMHA have five hundred and thirty two cottages spread across the former coalfield, which stretches across the County of Northumberland, North Tyneside and Newcastle Upon Tyne.

The Challenge

Solar PV TIC 29.7kW DNC 25.2kW

The objective would be to reduce their energy bills and provide FiT income for reinvestment in housing sector. NAMHA saw Solar PV as an ideal way to decrease the living expenses of their residents. However, the housing stock itself consisted of properties facing all directions, some with some fairly difficult shading issues so it was important to find a solution that would ensure NAMHA could capitalise on any technology installed and maximise the benefits of the system for both the tenants and themselves.

The Design

Many of the bungalows were in terraces. This meant systems could be either separated and made smaller in size or created in long arrays flowing across the roofs but this would have meant mean splitting the systems wiring to the individual properties. With a conventional string inverter this is of course possible, however the choice of an Enphase micro-inverter system saved many complications with strings and the difference between system potentials.

Reliability Harvest / Performance

With 400 homes having systems fitted, reliability was paramount. System downtime had to be minimal, so an Enphase system was selected based on its reliability, availability and 20 year warranty.

The Solution

The installation was spread over 39 sites within the Northumberland area, and the project was divided into 10 phases of works. Each site’s topography and solar access level was unique, requiring a technical and shade analysis survey for every individual property. In total the NAMHA project involved approx 4000 modules. The Solarworld SW250 60 Cell Black Mono was chosen, along with the Solarworld SunFix mounting system. The majority of the installations featured slate application which came with its own challenges. To combat the timescale encountered with slate application, a revolutionary new roof bracket was used: the Solar Limpet. This enabled slate application without the need to remove a slate. The bracket is fitted on top of the slate and through simple yet regulated installation provides a compressed fix through to the properties timbers rather than any pressure or load being applied to the slate. The Limpet reduced installation time by half and comes guaranteed with no leaks, provided it is fitted to the manufacturer’s instructions. The bracket is MCS accredited and provides an effective solution to a previously a tedious and time-consuming task. The project will also see approx 4000 M215’s fitted with a large majority being monitored through Enlighten for maintenance and monitoring. Aside from the Envoys, GSM MCS approved Generation Meters have also been fitted in the form of the Elster A100C. The installation is registered on a portal and the information and generation figures are reconciled daily to provide bulk submissions for the Feed-in Tariff.

The Result

  • Tenants energy bills reduced
  • 7m kg CO2 to be saved over 20 years
  • Future proofing of housing stock
  • Income generated for reinvestment
  • Increase in nett worth of assets
  • Improved local unemployment levels