A solar system which is pleasant on the eye

Mark Morris of Breedon Generon gets up close and personal with the UK roofing industry’s new solar roof power solution.

Racking up 2,000 miles on a friends and family tour of the UK was how we spent a couple of weeks last summer.

While the weather was mostly sunny, it was quite frankly staggering to see that only one of the many new housing developments we spotted en route was making use of the roof for solar energy in any respect.

Whether that development was using traditional bolt-on panels or one of the more recent integrated photovoltaic systems I cannot remember, but I do know they were easy to spot even from hundreds of metres away. 

Whether bolt-on or in-line, they had one thing in common – they unhappily undermined the aesthetics of the otherwise stylish properties. I wanted to reiterate the statement by our now King Charles that a glass and steel extension to the National Gallery was “a monstrous carbuncle on the elegant face of an old friend.”

This situation sums up the tradeoff housebuilders and developers have had to make to date. If they could justify the investment in solar and have their buyers enjoy the benefits this investment can bring, they all had to be willing to live with the blemish that came with the addition of large solar panels, to the disadvantage of the natural beauty of a well-designed roof.  

So, it is good to see that after a few industry false starts with recycled plastic roof tiles and others, a new participant in solar roof systems has sneaked in under the radar – in the form of a unique whole roof concept that virtually invisibly adds wow-value differentiation to a new home.

This next-generation in roof renewables comprises a 3.2mm monocrystalline tempered glass PV panel that has been securely attached to high-density premium thin-edge 330mm x 420mm slate-coloured roof tiles. The tiles are fitted in the same way and at the same time as the standard roof tiles, and once laid, each simply plugs into the next. 

Unlike other PV systems, electrical connections to the inverter can then be carried out on-site by an electrician. The overall solar output is based on the number of tiles fitted, with typically, 260 solar tiles required to generate a 4kW PV system – the benchmark for family homes.

The solar tiles are fixed in place on spaced battens using storm clips with a minimum 5cm ventilation gap to ensure optimum temperature control. Each tile is fitted with a weatherproof junction box and interconnecting cables – the positive terminal merely connects to the negative terminal of the adjoining tile. The final positive and negative terminals are the only two cables that pass through the roof felt for connection to the inverter.

Once fitted, the MCS-certified system, which meets key safety and CRT performance standards, then connects to the remaining PV infrastructure, delivering a slick and seamless integrated solar roof, without any aesthetic compromise for the homeowner. In addition, because the system is similar to a standard tiled roof in every respect, waterproofing integrity is guaranteed from the outset.

The solar roof tile system jettisons the need for specialist PV installers to fix solar panels and their associated mounting materials as they are easily installed by a professional roofing contractor with minimal additional training. This reduces the time and overall cost of installation, regardless of whether it is new-build or a re-roof, which also helps roofing contractors stay competitive and innovative in an increasingly uncompromising climate.

These solar roof tiles are designed to be highly durable and to withstand the harsh weather conditions the UK is progressively suffering from, including heavy rain, hail and high winds. Even without this, they have a longer lifespan than traditional solar panels and require less maintenance over time, owing to the securely integrated nature of their design, which even negates proofing them against pigeons and other vermin. 

And if a single tile does stop working, it does not affect the whole system, due to a bypass diode in each tile that prevents the entirety from going down. The interconnecting cables are designed so they cannot be fitted in the wrong sequence, leaving it extremely rare for tiles to fail during operation. In such cases, the faulty tile can be located either by testing each tile or using a drone with a thermal camera. 

The system also features a dedicated app for homeowners to track real-time data on its energy production on their smart phone.

Developed in partnership with a leading European roof tile manufacturer, which has made a significant investment in Europe’s only dedicated solar tile manufacturing facility, the award-winning system’s speed and ease of installation is expected to help housebuilders and developers under increasing pressure from the latest Part L Building Regulations for the conservation of heat and power, to keep viable pace with the growing renewables sector. 

While they have an increasing number of energy saving/generating solutions to choose from, including ground source heat pumps and mini wind turbines, now they have a solution that differentiates their offer, adds value to their brand, and maximises the potential of the largest area of a house, all while maintaining its aesthetics.

Growth forecasts for solar roof products are very promising. Roof top solar power is now installed in more than 900,000 UK homes and many industry analysts predict double-digit annual growth over the next decade. 

Much like the first mobile phones, whilst innovative for their time, in hindsight look clunky and impractical, so traditional and integrated solar panels look set at last to be replaced by more innovative architecturally acceptable solutions that deliver the same level of performance without compromising a roof’s aesthetics.