ENERGY SAVING TIP #3 (Lighting)

Did you know that a single inefficient light can consume more power than a modern TV or fridge??. Addressing lighting energy consumption not only saves you on the energy bill, it significantly reduces the size of your solar system and reduces carbon emission thus you indirectly participate in helping “save the planet”. Measures to save energy on lighting include:

1. Avoid overlighting- Sometimes rooms are given ridiculous lighting levels that are not necessary, and occupants might not even realise it. Generally rooms require 50lux for bedrooms, 100 lux for kitchens, 300lux for bathrooms [3]. Get expert advice on lighting optimisation from Rentech’s Electrical Consultants and Electricians to optimise your lighting layout.

2. Dust off your bulbs!

A simple thing like dust on your bulb can result in one buying more lights than necessary as dust can reduce brightness and luminance of your room. Dust notoriously prevents electronic equipment and devices from running efficiently [4]

3. Turn off the lights please!!

Have you ever come across an UNOCCUPIED office building with INTERNAL lights turned in the evening, or a tower/streetlight (unfortunately a common sight) turned on during the day and wondered what in the world is going on? Well there is a serious waste of energy going on!!... and unfortunately you might also be doing the same at home. To avoid this the following can be done: (i) turn off the lights in those rooms which are rarely constantly occupied like toilets, study rooms, store-rooms (ii) external lights- install day-light switches that automatically turn off your external lights when there is sunlight (iii) use motion sensors for commercial applications like car-park area and ablutions/corridors that turn lights on when there is motion

4. Use dimmers- Installing dimmers for your lighting system is easier than most people think. Dimmers allow you to reduce lighting intensity e.g. in the office during the day or at dawn or dusk where you get assistance from natural light

5. Optimise Luminance- sometimes it’s not the “brightness” of the light but just inappropriate height, position and distribution that reduces lighting effects in your room, which can result in you installing more lights than necessary. Get expert advice on lighting optimisation from Rentech’s Electrical Consultants and Electricians to optimise your lighting layout.

6. Convert fluorescent lights to LED

This conversion is not always possible due to safety and other issues, however most of the times it is possible. If your fluorescent light has mains frequency control gear, then retrofitting kits can be used in the conversion to LED lights [1]. Retrofitting (using old light fitting for new LED lamp) can only be done if (i) your lighting fitting is not too “old” (preferably less than 10 years old) (ii) your lighting fitting is not damaged. If the fitting is not good enough then replacement of the whole system (lamp and fittings) will have to be done.

7. Use study lamps

Sometimes turning off/dimming the main room lighting and simply using just the focused bedside study-lamp for that late-night reading can do wonders on lighting energy bill in the long term

8. Use external solar lights with integrated batteries

For external lights it’s best, wherever possible, to just install a separate solar lighting system with panelling and integrated batteries. This system will take your external lights off the grid (ZESA) and reduce the size of your solar system. Please see our catalogue and pricing of solar lighting at https://www.rentechsyst.com/shop

9. Do away with artificial lights!!

It makes absolutely no sense to use artificial electricity using lighting when there is free available natural lighting from the sun, during the day. To start with, from the onset have your home or building designed such that it has adequate well-positioned windows, and optimised room orientation that allow as much daylight into the space as practically possible. On chilly days where you won’t be too keen to open your windows, make use of window blinds to let the light in. Transparent portions of the roof and sky-lights also help reduce the need for artificial lighting.

For FREE tips on Energy Optimisation of your system please do get in touch with our Engineers https://www.rentechsyst.com/blog

Sources:

1. Carbon Trust; “How to use retrofit kits to convert fluorescent light fittings to T5 fluorescent or LED lamps”

2. 5 Ways to Save Energy on Lighting | Payless Power

3. Illuminating Engineering Society

4. Save Energy with Spring Cleaning | SmartEnergy

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About Author:

Lovewell Chitiyo is a Mechanical Engineer with 15 years experience in the building services Engineering consultancy, renewable energy systems and sustainable design fields. He is currently studying Masters in Renewable Energy at Stellenbosch University in South Africa

Lovewell is an Accredited Professional with the Green Building Council of South Africa for Existing Buildings Performance and New Buildings; Interiors, holding several qualifications and certification in Renewable Energy and Sustainability.

Lovewell also has vast experience in design, supervision, installation and commissioning of several projects locally and regionally in the last 15 years.