Construction World October 2015

don’t compensate well for excess electricity that is exported onto the grid. A rooftop plant should be incorporated into an organisation’s long term operational plan in order to optimise the business case. We always recommend that we optimise the PV plant size to what the load should be, not necessarily what it is currently,” said Turner. Advantages There are a number of advantages to incorp- orating PV into building design at inception: 1. Incorporating solar power into the original concept and plans will result in a system that is aesthetically integrated into the overall design and simpler to install. “Well-integrated plants can add to the appearance of a building, and by planning ahead, the available roof area can be designed to accommodate the optimal size plant with simplified cable routing, and objects on the roof such as chimneys and aerials can be placed where they won’t impact the performance of the PV plant.” 2. In roof PV installations, the building will be designed to carry the weight of the PV plant, as well as optimising roof angles to get maximum solar exposure. “It tends to cost more to add PV post-build than incorporating a PV plant in the original design. When working on existing buildings, if the original roof was not designed to carry the additional load of a PV plant, the cost of strengthening the roof can negatively impact the business case.” 3. A PV plant that is planned upfront can be better integrated with back-up power solutions “By adopting a holistic systems view when designing a building, a PV plant can be better integrated with available back-up generation and storage technologies, reducing costs and

improving operations. This is important as business owners grapple with the challenge of energy security and cost-effective solutions to loadshedding” 4. It is often easier to combine the cost of the rooftop PV plant into upfront asset financing structures than to finance these projects at a later stage. “Although juwi doesn’t cater to the residential solar market, it is probably easiest to use the example of a residential PV system to illustrate this. A R100 000 solar energy solution would be easy to absorb into the original bond amount if it was integrated from conception, whereas financing this amount without a secured loan at a later stage can be more complex. It’s almost always cheaper and easier to finance upfront,” says Turner. With the rapidly increasing cost of electricity in SA, RE is the logical next step for those companies that have already implemented all economically viable energy efficiency initiatives. According to Turner, juwi has been able to undercut tariffs of 80 - 90 cents per kWh, which “is exciting, because it opens up a huge market for rooftop solar all over South Africa”. ∞

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