Frugal innovation: why solar PV should be higher on housebuilders’ agenda

Paul Hutchens is Director of Midlands-based solar specialists, Eco2Solar. He is a board member of the Solar Trade Association, the UK’s leading solar industry voice, and Chairman of the STA’s New Build Working Group which aims to inform governments, councils, house builders and consumers about sustainability in housing. Here, Paul explores the most cost-effective ways for housebuilders to innovate and drive long-term sustainability from their developments.

Housebuilders face a number of challenges in getting a new development off the ground; securing the right land at the right price, obtaining planning permission, making sure planning requirements are met, and – crucially – putting in place a strong supply chain to design and complete the build.

Just about the only thing that isn’t presenting a challenge at the moment is actually selling the houses. With interest rates set to remain low this year, cuts to stamp duties and growing demand from first time buyers, the market looks buoyant – for the foreseeable future, at least.

In such a favourable market, the incentive to pioneer renewable technologies in the new build sector is low; the only thing driving this incentive is the sustainability targets set by the government and local authorities. So why should these technologies be higher on housebuilders’ agenda?

Leading the way

As well as needing to meet nationwide building regulations per house, housebuilders are given sustainability targets by their local planning authority, which specify how much energy should come from renewables per development site.

These targets vary significantly depending on region; London, the South East, the Cotswolds and Scotland are currently leading the way, with as much as 20% of site-wide energy on all new build developments required to come from renewables.

But with the very real prospect of government targets to build carbon-free homes within the next few years, coupled with a growing societal focus on more sustainable living and the volatile global energy market, regional energy targets will continue to increase, and it’s happening already.

In the future, we’re also likely to see a reduction in our reliance on the power stations, with homeowners able to produce greater amounts of clean, locally-sourced energy that’s better matched to their unique usage needs and even selling surplus energy to their neighbours in the same street, village or town.

This concept may seem like a distant pipe dream at the moment, but as people become more conscious of the available resources within their home created by solar energy, a sharing economy will become much more commonplace.

The right solution

So what are the best energy-saving options for housebuilders at the moment? At present, there are numerous materials and technologies developers can use to support energy targets; they could install more insulation and better windows, introduce solar thermal and heat pumps, fit solar tiles or even consider installing electric vehicle charging points, which some authorities are even specifying on plots right now.

But the problem with many of these solutions is that they are expensive to install and require constant maintenance throughout their lifetimes, which is an off-putting prospect to both developers and buyers.

Housebuilders seek technologies which are the most effective, represent the best value and which are aesthetically the most appealing, and the single most effective way to for them to achieve these objectives – as well as meeting energy targets – is solar PV.

The benefits are well documented; the price of solar PV as dropped by over 80 per cent in the last eight years and that initial lower cost comes down even further when multiple panels are installed across the same plot. And while solar roof tiles may be growing in popularity, they are currently twice the price of solar PV but offer only 90 per cent of the efficiency.

As well as being quick and unobtrusive to fit, solar panels don’t require any maintenance once they’ve been installed, and aesthetically, there have been significant developments. Gone are the days of the old blue panels jutting out eight inches above a roof; we now embed all-black integrated systems that sit directly in the roof and appear part of the house.

Solar PV is also quite a flexible technology which can be closely adapted to housebuilders’ needs. There are multiple options for colours, system types, flashings and fittings that can be matched to fit a particular house or development; this flexibility also enables us to find the most cost-efficient solution for each project.

Avoiding common pitfalls

But although the benefits are clear, we often see housebuilders encounter the same pitfalls. For instance, developers may choose to install solar PV through mechanical and electrical contractors, who will then subcontract out the installation process to solar specialists. This seems like the simplest solution because developers can put everything through one order with one contractor; but this can cause countless problems.

Firstly, there’s cost; contractors will often add on a much higher margin to existing quoted solar installation, and if they are aligned to a particular solar supplier or technology, they will specify these materials without necessarily taking into consideration whether there’s a better, more cost-effective solution available.

Secondly, non-solar specialists may not be up to date on the latest technologies and innovations, so if the energy targets presented by a local authority or consultant are inaccurate or out of date or based on old-fashioned panels, the contractor may not realise there’s a better or cheaper solution. One developer we worked with had given 60 plots with solar PV to a roofing contractor, who installed a clumsy on-roof system that cost more £60,000 more than a more attractive in-roof alternative.

Thirdly, there’s the solar supply chain and the numerous issues we see when the chain breaks down. For example, on one site we assisted on where PV was carried out by a roofing contractor, the roofer assumed the developer had completed the application for connection with the National Grid, while the developer assumed it had been done by the electrician, resulting in the Grid refusing connection at the handover stage.

Additionally, we have previously seen energy consultants propose systems to be installed in small arrays with very high ballast levels, meaning higher costs and increased loads exceeding structural capacity.

Therefore, it’s essential to use a technology-neutral solar PV specialist who can recommend the best systems for your development and create CAD drawings for your architects, with expertise in meeting energy targets and liaising with the relevant authorities and DNOs, SAP Assessors to remove any pitfalls along the way.

Looking to the future

When we look at the homes of the future, solar PV will play an even more integral part in the technologies we use to drive more sustainable lifestyles. With the smart technologies we’re seeing coming onto the market, homeowners will have complete ability to control the energy in their house using a single app. As these technologies become more widespread, homeowners will become much more accustomed to monitoring and manipulating their home energy by switching things on and off remotely through smartphones and devices.

Artificial Intelligence will mean a house knows its owner has kilowatts of PV available from their roof system; that they have nothing switched on during the day, that they normally get home around 6pm in the evening and that’s when they begin using energy. It also knows that the next door neighbour is at home during the day,
so she could buy the spare available energy being generated.

Then there are the innovations in block-chain technology currently happening in Germany, which work by providing a shared ledger of all available energy within a user’s home, and instead of our current model of a user paying for another user’s available energy via the National Grid and utilities companies, it enables direct billing and payment between users.

When all of these systems are tied in with technology like battery and EV charging and home security sensors, we are inevitably moving towards a much more automated home.

For housebuilders, we could begin to see these innovations offered to buyers as part of long-term maintenance contracts where home sensors can detect things like burst pipes, or buyers could be offered ‘bolt-on’ home automation packages that enable them to control their energy security. Until then, solar PV continues to offer housebuilders an innovation that best meets their targets; and their budget.