Protecting solar investment

A Liverpool primary school's new photovoltaic system employs a variety of flexible conduit systems for cable protection

Posted by Dave Higgitt | April 10, 2015 | Sustainability

• #photovoltaic
• #solar-panel
• #kingsley-community-school
• #feed-it-green
• #flexicon

As part of a regeneration scheme, Kingsley Community School in Liverpool is installing a 24kW photovoltaic system in order to reduce its long-term electricity bills and its carbon footprint. The roof system will generate an estimated 19,270kWh per year, which equates to an income and savings of £4,187.36 per year. Over its projected lifespan of 20 years, this would amount to £83,747.20.

To protect the installation’s cabling, installers Feed-it-Green opted for Flexicon’s flexible conduit. Feed-it-Green director Mark Reynolds explains why: “A photovoltaic installation is a long-term investment and it is important that it stays up and running throughout its projected lifespan. It is therefore vital to specify top-quality products. Sadly, too many installers overlook cable protection, which is a mistake since this can have a serious affect on a system’s long-term viability.

“The cabling is exposed to all that the British weather can throw at it. Not only do the cables need protecting from UV light, ingress from water and dust and temperatures ranging from below freezing to a hot summer’s day, but mechanical forces due to wind and other factors such as rodents or birds.

“Since this is a public building, we also need to protect the cables from vandalism and potential cable theft, so mechanical protection is vital. This is particularly important because cabling from photovoltaic panels have DC current running through them and are live when it is sunny, so there is a serious safety risk for people.”

The project used different protective conduit systems from Flexicon, dependent on the potential hazards faced. Feed-it-Green specified Flexicon’s FPAS non-metallic conduit to protect the cabling on the roof. This provides UV resistance, compression strength and when used with the FPA fitting has an IP rating of IP66. The conduit was used with the company’s FPA T-pieces, allowing cables to branch off to connect to the individual photovoltaic strings.

Down the side of the building, a coupler was used to connect and convert the FPAS system into a metallic conduit called FSU. This system then fed underneath the eaves of the roof and inside the building to the inverter. As a metallic system, it has the mechanical strength to protect it from vandalism or theft. It can also bend around the eaves and when used with compression fittings has an IP65 rating. Flexicon has also supplied flexible conduit to protect all the internal cabling to the inverter and then from the inverter to the distribution boards.

“This project clearly demonstrates the benefit of working with a manufacturer who can offer a wide range of products to match the specific hazards faced by the cabling,” says Mark Reynolds. “Flexicon’s technical help will help ensure that this installation will remain working for many years to come. The flexible conduit systems that we used were easy and quick to install.”

www.flexicon.uk.com