New Build & Construction PV Projects
- Solar PV can still provide over a 10% ROI with a 5 – 7-year payback
- Installing solar affords you greater protection against the rising costs of electricity
- CO2 reduction and improved energy efficiency measures for your building
Points to Consider when Installing Solar PV
In delivering new build and constructions renewable energy elements there are some key factors that must be considered and are often overlooked, ultimately to the detriment of the client.
- DNO & Regulatory Compliance – prior to installing a system anything over 3.68 kW per phase must have approval from your local DNO (district network operator) to ensure the local infrastructure can handle the additional load potentially being back fed. Without this connection agreement in place, any installation connected to the grid is at risk of being terminated with the sole authority sitting with the local DNO.
- Planning Conditions – planning must also be considered within an installation, typically a 1m envelope is required around the sides to comply with Permitted Development. Modules that protrude over the ridgeline on a pitched roof or are greater than 1m in height from the tallest part of the building’s structure on a flat roof will need formal planning consent. Equally any building that is listed or sites within a heritage or conservation zone will need attention. It is always worth confirming the requirement with your local planning office.
- System Design – it is important to design a system that meets the needs of you the client. There are many considerations here but importantly it is about balancing generation with consumption. The best financial returns are now realised through consuming what you generate hence the system should be tailored to these factors. Whilst steep pitched, south facing elevations create the higher yield, this is limited to a particular window of time within the day hence low-pitched, east/west facing roofs generate for longer periods throughout the day thereby more closely mirroring the load.
- Structural Calculations – solar panels not only apply additional load to your roof but create wind uplift so you need to be sure your roof can handle the additional pressure. These calculations are provided during the design phase to enable them to be signed off by a structural engineer.
- Integration with your Structure – your roof and it’s warranty to be dually noted, and in full compliance to avoid invalidation
- Warranties & Bankability – these are assigned to your system and not the contractor so you are not at the mercy of your installer. You want to take comfort that the manufacturer is here to stay and can underwrite the warranty it provides. It is always recommended that Tier 1 and bankable components are used. Different length warranties are offered and it is always proposed that the following minimum periods are sought; Modules – 10-year product & 25-year performance / Inverters – 10-year product* / Mounting – 10-year product
* inverters are most likely to fail hence an inverter swap out provision is always suggested.
- DC Isolation and Fire Risks – increasingly common now are unforeseen issues and costs post installation relating to a significant uplift in your building insurance due to additional risks fire risks posed by the DC side of the installation, known as DC arcing. In some areas such as London, fire crews will no longer put out fires if they can’t be sure that the PV system can be isolated at roof level. Typically DC cables run from the roof to the inverter(s) in a plant room, however by installation optimizers at roof level this provides isolation at panel and roof level thereby mitigating the risk and minimising any significant uplift on your insurance.
- Quality & Cost – many of the factors and potential additional costs set out above are ‘hidden’ and don’t necessarily come to fruition until your installation has been completed. It is often then too late to recoup these costs from your contracted company and you are left with an unexpected bill. It should also be noted that solar PV contractors are often twice removed from yourself the client (main contractor – (M&E consultant) – M&E contractor – PV contractor) hence significant additional ‘costs’ and margins are often applied. All of these ultimately adversely affect your returns. It is why we at your Eco Construction always prefer to engage with you from the onset and to work directly with clients, developers and architects alike to maximise your return and meet your requirements whilst reducing costs and ensuring quality throughout. It’s an investment to be realised and one for which you need a partner you can trust.