Flow with the current and win the energy battle

Since 2008, the V&A Waterfront has invested R30-million into energy efficiency, water savings and waste recyling. (Photo: Growthpoint)

Since 2008, the V&A Waterfront has invested R30-million into energy efficiency, water savings and waste recyling. (Photo: Growthpoint)

The reintroduction of load-shedding hit the headlines late in 2014, causing a mild panic for those who had not already installed measures to deal with the phenomenon after the last round a few years ago. The scheduled power outages seem to have slowed up in the last couple of months, with Twitter outrage — the quickest vox pop of consumer sentiment — slowing down to a dull moan rather than an outraged howl at each instance. 

But the prospect of more load-shedding has certainly not gone away, and property owners and tenants are not only confronting the inconvenience and costs associated with breaks in electricity, they’re facing rising tariffs, seasonal cost spikes, and the prospect of time-use tariffs becoming a reality in the next few months. 

The costs of load-shedding go beyond business activity that cannot take place because there is no electricity to power production. Unexpected power outages damage equipment that needs to be shut down gracefully, and there are also practical considerations like people getting stuck in lifts, and the associated trauma of being confined in a small environment for the duration of a power outage. 

It’s clear that no matter what we say about it — in opportunities for formal public comment or around the water cooler — that the costs aren’t going to change in any direction but upwards. Rather than lamenting this irrefutable fact, the next strategy is to find ways to control or reduce energy consumption. 

It’s simply not practical to tell people to work less (although one could ask them to work more efficiently), or use less electricity in their day-to-day production — so it falls on building owners to make interventions that make their properties more appealing to businesses that want to keep their energy costs under control. 

One of the biggest consumers of energy in a building is the heating, ventilation and air conditioning system (HVAC). Energy efficient design has seen great success in reducing this need in many newer buildings that use natural ventilation to limit the need for air conditioning. 

But this is not always possible in larger buildings, or in older buildings where renovation costs to change the demand for HVAC are simply too prohibitive. 

AHI-Carrier, the company that claims to be the inventor of modern air conditioning, says that a building owner can start looking at saving costs by firstly investigating the efficiency of the existing HVAC plant, and then examining the possibility of using variable speed drives on pumps and fans to reduce start-up demand and overall usage. Consulting engineers are able to assist with this.

Also important is to ensure that the cooling towers and auxiliary equipment are operating efficiently and are well maintained. AHI-Carrier has found a number of buildings and property owners around the country decreasing the recommended monthly service to bimonthly or quarterly services due to costs. Maintaining the equipment frequently not only reduces downtime, it lowers costs. For example, compressors failing through a lack of preventative maintenance can be very expensive. 

Equally, if water treatment is not done regularly, the tubing may get damaged, which means machines will run at higher condensing temperatures, increasing energy use and causing additional wear and tear to the entire system.

The same applies in air-cooled chillers. If the condenser coils are damaged through irregular cleaning, the same can happen: machines run at higher condensing temperatures, using more energy.

Otis, one of the world’s largest manufacturers of lifts and escalators, has seen an escalation in the number of electricity-related service calls since the implementation of load-shedding. The company offers an automatic rescue device that is essentially a backup device for a lift, which moves it to the nearest floor and opens the doors, allowing safe exit in the event of a power failure. 

Lifts can also be connected to generators in buildings that are fitted with this equipment, allowing one lift to operate normally and others to complete the automatic rescue service. 

For new installations, its Gen2 Switch lift includes a rechargeable battery that can power the lift for up to 100 trips between eight floors. It can also be connected to solar panels and uses up to 80% less energy than older lifts. 

Other interventions suggested by AHI-Carrier include an energy management module for HVAC that is connected to the chillers and can be linked to the building management system. It can be programmed to inform the system about occupied and unoccupied areas. One can also have a night setback point, which reduces the capacity of the chiller when building occupancy is low, assisting in reducing overall energy usage. 

On the heating side of HVAC, heat recovery or partial heat recovery systems (also called heat pumps) are available. They produce hot water as a natural part of the chiller cycle, and can be used to replace costly geysers for showers (for example in gyms) and in kitchens. Typically a storage tank is installed, and the hot water pumped into it from the heat pump is then drawn off to provide hot water to parts of or throughout the building. 

carbonTRACK SA has introduced a locally made, intelligent energy management system that can be used in domestic or commercial applications. It includes energy monitoring, control and remote switching, and can manage the energy consumption of a home or business via a smartphone, tablet or personal computer. 

The company’s Irvan Damon highlighted how sometimes the simplest interventions can make a difference, citing the example of a worker in a fast-food outlet who came to work an hour early every morning to switch on and heat up the cooking equipment — when in fact that cooking equipment only required a 10-minute warm up. That’s 50 minutes of wasted electricity — used by high demand appliances — every day. Controlling the up-time of such equipment can reduce energy consumption — and costs — significantly. 

carbonTRACK technology can “see” electricity use in a home or business, and uses clever algorithms to switch devices on and off as required so as to minimise their electricity consumption. A proprietary communications stack allows remote switching of devices in less than three seconds, using robust telecommunication networks at a radically reduced cost. The end results are electricity savings of up to 30% or more. carbonTRACK also offers Eskom the ability to remotely switch major loads such as geysers and pool pumps during peak load events, improving grid stability.

Also on the horizon for commercial property owners is the proposed carbon tax, with the relevant bill set to go out for public comment later this year, which will add to commercial energy users’ costs. Aimed at large users, implementation of the carbon tax is expected to simultaneously see a reduction in the electricity levy. 

It will introduce a low tax burden for the first five years, at an initial proposed cost of R120 per tonne of CO2, with an expected escalation of 10% per annum. 

Intended to support South Africa’s commitment to the global arena that it will reduce carbon emissions, the carbon tax has been cited as yet another burden added to the cost of doing business in South Africa — although the government stance has been that, if revenue recycling is included in the economic model of the approach, that the impacts of the carbon tax are manageable (according to Salem Fakir and Manisha Gulati in this paper on September 20 2013). 

Commercial property owners and developers would do well to look out for the publication of the bill and to understand fully its implications for the future.

Top tips to reduce energy consumption

The task of reducing energy use (and electricity costs) in a commercial building may seem daunting, but it’s true that every bit counts. Once building owners and tenants start making changes to the way that “things have always been done”, it will be easier to make more positive changes. There’s no doubt that the most meaningful (and inspiring) change will be a reduction in electricity costs — so try implementing these changes in your built environment and measure the results. 

Check all equipment to make sure that it is running properly, including air conditioners, geysers or boilers, printers and any other plugged in device that draws electricity. A device with a fan that is working harder than it should, or a thermostat that is running at too high a temperature all use more electricity than they really need to. Add up the savings that can be made across a whole building by checking this simple thing, and it will become clear that maintenance is actually less expensive than repair. 

Chat to people who use printers or other devices that are left on standby overnight. As much as 6% of electricity use is those standby lights, or devices left switched on overnight “just in case” someone might want to use them overnight. Printers power on far more quickly than they used to — so the excuse of it taking too long for a printer or photocopier to warm up is no longer plausible — and there’s no reason why monitors should not be switched off overnight.

Install motion sensors on your lights, particularly if you have a workforce (including cleaners) that works at night. These sensors mean that electricity will only be consumed when someone is in a particular space, reducing electricity consumption. 

Change to CFL or LED light bulbs wherever possible. These use less energy, last for longer and produce less heat — which means that the load on your air conditioning system is also reduced. Innovation means that you can choose warm or cool colours of light. 

Locate as many work stations as possible near windows to use as much natural light as possible during the day. The added bonus of a view of the outside world is also known to boost worker wellbeing. 

Install energy management technology that can adapt the use of power-hungry services at off-peak times. If your building has an overnight security team, it’s their area that needs air conditioning, not the whole environment, for example. 

Have your building assessed by professional energy consultants to see how much energy you really use (and how much carbon you’re pushing out into the atmosphere), and get professional advice on interventions you can make in the building, or in the behaviour of its occupants. 

Renovate wisely. If you’re planning to renovate or upgrade, there are numerous interventions that you can make to boost the energy efficiency of your building, and reduce its energy consumption in the future. These include changes to the building envelope, upgrading lighting systems, replacing HVAC systems with newer, more energy efficient alternatives, or even installing double glazing – an intervention that is as effective at keeping heat out as it is at keeping out the cold. 

Talk to the people who occupy the building. Learn more about usage patterns, and engage with them to discuss ways of saving energy. No matter how sophisticated the intervention that you put in place is, it will only succeed if a building’s occupants understand why they may have to change their habits — and they can see the direct benefits of doing so.



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