Running an air-conditioning unit at full tilt to cool down one part of a building while a boiler blazes away to heat another part of that same building seems senseless – but it's surprisingly common in New Zealand's commercial buildings.
Wasting energy at such large volumes is not only bad for the environment, it's bad for business. Large companies can unwittingly spend thousands, if not millions, of dollars on wasted energy every year.
The Energy Efficiency and Conservation Authority (EECA) says many businesses could shave up to 20 per cent off energy costs – and many fixes are inexpensive or even free, immediately effective and boast short-term payoffs for the investment. According to some of New Zealand's leading energy experts, here are some common ways businesses waste energy.
Heating and cooling systems
Ben Thomson, Divisional Manager, Enercon: "Often HVAC [heating, ventilation and air cooling] systems are wasting huge amounts of energy without anyone knowing. When you consider HVAC usually accounts for at least half of a building's energy consumption, a 10-20 per cent energy saving can reduce operating costs significantly."
Thomson points to one business whose HVAC systems were needlessly operating 24 hours a day, seven days a week. In addition, adjacent heating and cooling systems were fighting each other due to poor control logic.
"Because no one was at the facility at night and the heating and cooling effectively cancelled each other out, the issues were never noticed."
Thomson says these types of issues occur in most commercial buildings, typically because they have not been optimised for their actual use compared to the hypothetical assumptions used during design and construction.
New technology vs basics
Anne Herrington, Director, Smart Power: Those getting started with energy efficiency may be tempted to invest in new, trendy and 'smart' systems. However, she sees doing this before cutting out basic energy wastage as akin to "buying shares when you have credit card debt".
A more cost-effective solution is to look at where the business is currently wasting energy and make simple tweaks instead that can greatly reduce energy costs.
"So many businesses waste money by leaving air conditioning on in the weekends and public holidays. It couldn't be simpler: turn off these systems when people are not using the buildings. Heating and lighting are for people, not buildings."
Smart metering can help identify where smaller sites can save money by reducing energy costs, by giving energy data readings every half an hour.
"With the advent of smart metering, you can monitor a business's energy usage and find out what's happening when you're not there. Once you have identified and cut down on major energy wastage inherent in the business, then think about investing in new energy-efficient technology that might require more capital."
Simon Ross, Energy Manager, Economech Analytics: "Until you show businesses a breakdown of where they waste energy, it is difficult to empower them to make a decision on reducing usage."
Simon points to benchmarking the energy "end use" in offices as part of advising clients how to improve their NABERSNZ ratings. When landlords and tenants can compare the energy usage of their office compared to other offices, they grasp that their buildings and processes could be more energy efficient.
This can help them identify the size of energy and cost savings which can be achieved from potential upgrades.
Poor commissoning of equipment
Erin Roughton, Managing Director, Emsol: "Many businesses waste energy and money by using poorly-commissioned equipment".
Businesses scrutinise purchases of new assets, however, they are not as diligent in checking these are operating as intended, leading to energy costs that far outweigh their purchase cost.
Roughton has seen businesses during the past 15 years make energy savings between 20-40 per cent by re-commissioning and optimising equipment. For example, an East Coast food processing business reduced its refrigeration discharge pressure by 2 bars and saved 17 per cent of energy use during the colder months of the year.
Another common problem is that equipment is often sized too conservatively, resulting in poor commissioning, poor efficiency, and excessive energy use. There are hundreds of commissioning checks and improvements available for all businesses that result in energy cost savings with little investment.
Information on how businesses can save energy is available on www.eecabusiness.govt.nz, or find an energy management expert in the Programme Partner directory (subs: www.eecabusiness.govt.nz/tools/programme-partner-directory)