Easy ideas to design your lighting to save power

One of the best ways to cut back on lighting-related costs is to use only the light you need and no more. This means you save power, and you may even experience aesthetic improvements as an added benefit!

Lighting engineer, academic and author Robert Bean says that while lighting improves our ability to see, there comes a point when there’s more light than we actually need.

“It has been found that although increasing lighting levels improves visual performance, after a certain level of performance has been reached, further increases in the lighting level bring relatively little improvement. In this respect sight obeys similar laws to the other senses such as hearing.” — Bean, Robert; Lighting Interior and Exterior (2014)

In other words, think about how you light your home in terms of what you need and want, rather than just flicking the switch and flooding the room.

Here’s how to achieve more efficient lighting in your home:

  1. Think about taking the task lighting approach 
  2. Light a room according to its function
  3. Consider our four off-the-wall measures to brighten a room and reduce energy use 
  4. Consider using modern Light-Emitting Diode (LED) lighting to replace older — and more inefficient — bulbs. 

The task lighting approach

Task lighting means focused, directed light, only when and where it’s necessary. It can apply to kitchen counters, desk lamps, reading lamps, cubicles and bathrooms. And it’s best to use low-wattage, ambient light to maximise cost-efficiency.

Task lighting reduces glare on things like tablet screens, computer monitors and television screens. At the same time it creates an intimate, warm and productive atmosphere.

The authors of Green Lighting — Brian Clark Howard, William J. Brinsky and Seth Leitman — recommend that the task light be to the side (the left side of right-handed people, and visa versa for left handed people) to reduce shadow. Keep the task light out of your eyes, make sure it is adjustable, and keep it directed towards the task.
LEDs make excellent task lights. They’re bright, energy efficient and you don’t risk burning yourself if you touch them.

Lighting according to function

Different rooms serve different functions. None of them need to be completely flooded with light all the time.
The bathroom is an example. Task lighting supported by ambient lighting works well.

Lighting designer Randal Whitehead told Forbes magazine about how to light a bathroom 

He said that using a pair of lights mounted either side of the mirror at eye level creates a shadowless scenario that’s best for tasks like applying makeup, and shaving. “Proper task lighting at the mirror is important,” he said.

Entrance halls are transitional spaces — moving from dark to light — and they’re not regularly used. Consider low, warm, welcoming light. A kitchen, on the other hand, could use ambient light supplemented with task lighting in alcoves, to create a pleasant and productive atmosphere.

For more information, read the books:

For creative ideas, visit Instructables.com 

Off-the-wall measures

Consider using any one of the following measures to brighten up a room and save on power use.

  • Painting a room in lighter colours will help to reflect more light. You can also save further by supplementing the room with big windows and skylights.
  • Other reflective surfaces, like white furnishings, bright cushions, glass tables, bowls and mirrors will help to make a room look bigger and brighter.
  • Re-arranging or reducing furniture can clear up space and improve flow. This also helps to eliminate shadows and dark corners.
  • Lighting up a feature point, like a table, or putting LED strip lighting onto shelves, can add ambience and mood to a room and reduce power use.

Significant power savings with LED lighting

A fast way to achieve power savings is to switch to LED lights. Until recently, people often ignored this option due to its relative expense. But falling prices have made LED bulbs far more affordable. Another major benefit is that LED bulbs typically use 90–95% less energy than incandescent bulbs — and they can last for between 10 and 20 years!

When you’re buying LED lights, look for New Zealand certified LEDs and be cautious of any that look like cheap knock-offs. Poor quality bulbs are unlikely to deliver the full benefits of LED lighting.

Stockists of LED lighting 
LED lightbulbs with Energy Star qualifications

The benefits of LED lighting

Unlike compact fluorescent light bulbs (CFLs), LEDs are free of toxins like mercury. They pose less of a fire risk than traditional bulbs because they give off very little heat — they’re less power hungry.

LEDs are also remarkably versatile. Many can be dimmed, and they’re efficient when it comes to producing different colours. You can also switch them on or off quickly, without the bulb ‘popping’. And they power up instantly, unlike CFLs.

Consumer NZ reports that LED replacements for standard bulbs result in substantial savings, with standard bulbs costing five times as much to run as their LED replacement.

Consumer NZ’s report comparing light bulb running costs

Considerations when choosing LED lighting

Look for warm white LEDs rather than cool white, which can be too bright and white for some. Install LEDs into ventilated fittings — they don’t like heat and may become dimmer if they get too hot.

Recessed lights in the ceiling (down lights) can cause significant heat loss up and out of the room. If you can, choose ceiling button LEDs (as opposed to CFLs or standard LEDs) as they provide the most efficient lighting in these circumstances. And LED wall lights may well be an excellent option when retrofitting any lighting in your home.

Installing LED lighting

To maximise your savings from the start, consider which lights you use the most and install these first. This will also help you manage the cost of switching over to LEDs.

If you wish to use your LED lighting with a dimmer switch, check the box to see that the product is suitable for dimming.

Read Consumer NZ’s report for more about LED lighting 

You can get LEDs as low voltage and mains voltage bulbs. The latter you can usually buy over the counter. Each has a base containing electronic components that allow for different power supplies and fluctuations.
Basic LED fixtures, such as a ceiling button LEDs, will most likely come with a built-in LED driver. Other low voltage LEDs, such as strip lighting beneath a cabinet or bigger garden lighting, may need an added LED driver.

This is because LEDs need specific voltage to work efficiently. Too little current and the results are poor; too much and the light may overheat, shortening its lifespan and causing fluctuations in light quality.

Watch this YouTube video for some DIY advice on how to replace a halogen bulb and transformer with an LED driver and bulb.