Jul 2018

Operations and Maintenance ensures that solar systems perform optimally

How to save through solar: 3 tips for commercial and industrial property managers

It’s long been known that managing commercial and industrial properties sustainably is not only about environmental, but also economic, sustainability. The good news is that for many facilities managers, managing properties sustainably can also deliver on their bottom line. One of the key areas of this is building electricity consumption – one of the largest expenditure chunks in any facility manager’s budget. As we know that reducing electricity consumption is a sure-fire way to save money, using a solar PV system to offset energy consumption makes sense. In this post we’ll explore three ways to ensure the economic benefits of solar PV are guaranteed in managing commercial and industrial properties.

Electricity consumption: a key concern for facilities managers in South Africa

In South Africa, electricity tariffs have increased on average 9% per annum for the last 5 years – and we may be in store for a further tariff increase in September due to Eskom’s RCA approval. These increasing tariff costs mean that it electricity is likely one of the top concerns for facility managers.  In fact, both cost savings and sustainability were highlighted as two “game changing” aspects of Facilities management for the next few years, according to the Facilities Management South Africa Knowledge Executive Report. With increased pressures on facilities managers to deliver high quality service at a reduced cost, electricity savings are imperative for facilities managers.

Much of this pressure has lead the property sector to invest in solar PV. Grid-tied solar PV systems can save properties between 20 – 40 % of their total energy consumption, making them an attractive option for saving energy costs. Increasingly, property companies and Real Estate Investment Trusts (REITS) are rolling out portfolio-wide solar PV interventions. The reason that this is so attractive is because of the rapidly decreasing prices for PV technology over the past few years, causing the costs to fall by 80% since 2009.

However, in order to make sure that a solar PV intervention actually saves money, there are a variety of factors to consider. Below are our three tips to follow in order to maximise the cost-benefit of the solar PV investment.

Tip 1: Implement in-house energy efficiency measures first

The lowest hanging fruit when it comes to building cost saving is often implementing in-house energy efficiency measures. If you haven’t already implemented in-house energy efficiency, this is the place to start for any kind of cost-saving, but it will also help any investment in solar PV to be more cost effective. A typical solar PV system has an output which ramps up in the morning, reaches peak output at midday, and then slows in the evening, such as the red line in this graph demonstrates:

typical solar PV load

Implementing energy efficiency measures to shift some load to mid-day when solar PV is at its peak production will ensure that you will fully utilise the cheaper energy when it is abundant. As an added advantage, peak tariff times are generally in the mornings and evenings, meaning that there will be an added saving. In order to fully optimise energy efficiency, implementing electrical submetering is a helpful way to analyse the energy load and understand the main energy-guzzling activities – in a typical commercial building this will likely be HVAC (air conditioning), lighting and electrical appliances.

The benefit of analysing a building’s load and implementing energy efficiency measures before procuring solar PV it twofold: it can not only shift the load more optimally as highlighted above, but it can also ensure that the solar PV system that is procured is the optimal size.

Khayim Fredericks, National Technical manager for Old Mutual, recommends looking into energy efficiency as a first measure.

“[I recommend] looking at [your] building and asking, is my building operating as efficiently as it can be, so that the solar system can be sized as efficiently as possible? […] When we explored the solar option [at Old Mutual head office], we had already reduced our consumption from 30 – 35%”.

Old Mutual solar PV system

Tip 2: size the solar system correctly.

As mentioned above, sizing solar PV systems correctly is key to enhancing their cost-reducing benefits. When sizing a system correctly, there are several factors that need to be understood, including:

  • The required energy load. This includes a thorough knowledge about the amount of energy that the building uses on a daily basis, including seasonal variations and power required.
  • The tariffs that apply. It is important to understand the energy tariffs that apply to the building, including what their tariff structure is and if peak demand charges apply. This will help when designing the solar system to see if excess energy stored in batteries might be cheaper than peak-demand municipal electricity tariffs.
  • High-rise, large commercial office blocks typically have less rooftop space available than sprawling retail centres. Understanding what roof space or ground is available around the commercial property is an important aspect of designing the solar system and its size.

What is wheeling?

Wheeling is the process of using energy from a location where it is not produced. Due to the way in which cities are set up, wheeling has great potential as it will enable building energy users with more roof space but less energy requirements, such as distribution centres or warehouses, to transfer power into energy-intensive urban hubs.

Tip 3: Add Operations and Maintenance into your ongoing energy costs.

Like any asset, the operations and maintenance of an installed solar PV system is paramount. Monetary savings generated by solar PV systems will be consistent if and Operations and Maintenance plan is followed. Factoring in the costs for operations and maintenance in the overall IRR of the solar system is important, because it will allow diagnosis of any possible problems early and thus ensure that the system continues to produce the predicted savings.

Make sure that you scrutinise what is included in an O&M contract. A comprehensive plan should include:

  • Access to software that provides real-time data on the production of the solar system
  • Remote monitoring and corrective action, when required
  • Access to technical staff who are able to assist with problem solving
  • Collating, analysing, and reporting on monthly and annual data
  • Inspecting the site and/or replacing components
  • Cleaning of the modules

A comprehensive Operations and Maintenance arrangement for your solar PV system will ensure that the system is running smoothly without you spending time diagnosing and troubleshooting, should there be a problem.

Operations and Maintenance ensures that solar systems perform optimally

By implementing in-house energy efficiency measures before procuring a solar system, sizing the system correctly for your load, and employing a comprehensive operations and maintenance plan, you will ensure the economic savings of a solar PV system on a commercial property.