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Energy Efficiency

Passive design strategies can dramatically affect building energy performance. These measures include building shape and orientation, passive solar design, and the use of natural lighting. If you are fitting out an existing building, or working with developers to fit-out a new building, you may be limited in how far you can go with these. Some key approaches include:

  • Develop strategies to provide natural lighting. Studies have shown that it has a positive impact on productivity and well-being.
  • Install high-efficiency lighting systems with advanced lighting controls. Include motion sensors and dimmable lighting controls where practical. Task lighting reduces general overhead light levels.
  • Use a properly sized and energy-efficient heat/cooling system in conjunction with a thermally efficient building shell. Over-specifying air conditioning and heating is one of the most common problems in modern buildings. Maximise light colours for roofing and wall finish materials; install high R-value wall and ceiling insulation; and use minimal glass on east and west exposures.
  • Minimise the electric loads from lighting, equipment and appliances. Look for appliances with the most energy stars.
  • Consider alternative energy sources such as photovoltaic or fuel cells now available in new products and applications. Renewable energy sources provide a great symbol of emerging technologies for the future.
  • Considering outsourcing computer services or using thin servers and LCD screens. Computer rooms use considerable amounts of energy.
  • Computer modelling is an extremely useful tool in optimising design of electrical and mechanical systems and the building shell.

Useful resources and information

Building Operation and Maintenance

Sustainable building measures can only achieve their goals when they work as intended. Building commissioning includes testing and adjusting the mechanical, electrical and plumbing systems to ensure all equipment meets design criteria. It also includes training staff on the operation and maintenance of equipment.

Over time, building performance can be assured through measurement, adjustment and upgrading. Proper maintenance ensures a building continues to perform as designed and commissioned.

Building Users' Guide

A useful tool to help tenants get used to and understand the new technologies and systems after a fit-out is a building users' guide, which might include:

  • commissioning timeframes
  • how to use the technologies (HVAC and lighting systems)
  • expectations of staff (energy, waste and recycling strategies)
  • who to contact (building faults or repairs)
  • fire evacuation plan.

The building users' guide should be tailored to your organisation's needs, and may be used as part of the induction process for new employees.

Useful resources and information

Appliances

Bathrooms

Hand dryers, towels or paper towels? The 'green' answer is not always straightforward.

In New Zealand, the energy source needs to be considered along with other factors when making this decision. With most of our energy coming from renewable sources, electric hand dryers are probably the first choice, followed by cloth, then recycled paper towels.

Kitchens

At present, there are no kitchen appliances with an Environment Choice ecolabel. However, the Energy Star labelling system has recently been introduced to New Zealand. All imported products should already carry these labels and from 2005 the scheme will gradually be introduced for New Zealand products. From 2006 Energy Star rated refrigerators and freezers will become available.

The Energy Efficiency and Conservation Authority (ECCA) also operates an Energy Rating Label scheme, designed to help you make an energy-wise choice when buying new appliances such as fridges and freezers, and dishwashers. The labels make it easy to compare the energy efficiency of models of the same size and class.

Refrigerator

Choose the appropriate size for your needs to minimise under or over loading. Position the refrigerator away from heat sources, including direct sunlight. Install it with a good 3 cm gap all around for good air circulation.

Dishwasher

Base your choice on the expected usage. If you are likely to run smaller loads more frequently, then a dish-drawer type dishwasher is more appropriate. For larger loads, or a dishwasher that is used only when full, choose a standard dishwasher with a good energy rating.

Copiers/printers

A large percentage of energy usage in an office is associated with office machines. EECA's Energy Star office products use less energy by automatically switching to 'sleep' when not in use, and/or saving power when on standby. Energy Star qualified computers, monitors, printers, fax machines, copiers and scanners are available in New Zealand.

Most printers and some copiers and fax machines use toner cartridges that contain heavy metals. Copiers and printers produce VOCs, ozone, styrene, toxic dust, heat and noise.

Pointers

Use Energy Star qualified computers, monitors, printers, fax machines, copiers and scanners.

Choose the appropriate printer and copier for your needs to minimise noise and heat.

Reduce exposure to toxins, heat and noise, by separating these operations from the rest of the office environment. A dedicated copier/printer room that is separately vented from the buildings main ventilation system is best.

Useful resources and information

Case study: energy efficiency

The main areas the Ministry for the Environment looked at here were:

  • the building management system
  • HVAC - heating, ventilation and air conditioning
  • lighting
  • appliances
  • hot water use.

The building management system

We chose an efficient building management system (BMS) for Environment House. The BMS monitors, measures and manages the overall energy use of the building including HVAC, lifts and security, and can also manage a sophisticated lighting system.

A BMS is vital in managing energy use and we anticipate it will deliver financial savings because it allows a building manager to avoid significant 'peak load changes'. Electricity retailers usually charge commercial buildings for a whole month at the rate that applies to their peak load during that month. If you can spread current energy use more evenly, you can save money.

Appliances

Kitchen areas on each floor service up to 50 people, so large refrigerators were required. No Environmental Choice eco-labelled products were available, so energy efficiency (Energy Star ratings and energy use) was the key criterion for selection. Currently several imported brands have higher ratings than local equivalents. The fridge chosen was the GRAM KS360 from Germany - a highly energy-efficient fridge.

The Ministry has reused dishwashers from its previous sites. Where new appliances are required, dish-drawers (Fisher and Paykel) are worth considering as these can do half loads and are highly water efficient. When loads are usually full, a standard dishwasher is recommended.

The Ministry analysed hand drying options and chose electric hand dyers in toilets. As most of New Zealand's electricity is supplied from renewable sources, we decided this option was marginally preferable to the paper and cloth towel alternatives.


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