Simple ways to reduce energy and add something special - by Lance Stewart, M.I.E.S

Matching the lighting control with the function of a space is called scene control. Being able to dim the lights, and 'set scenes' can and does save energy. And it looks better, because you can select the areas and objects you want lit in any given scene: turning down lights that don't need to be on at full intensity, while having others low or off when not needed at all.

Until recently, scene control was only possible with expensive architectural lighting control systems, which also required specialist programming skills and restricted your buying options because one brand of equipment would not talk to another. The lights you could control were typically incandescent which are inefficient and so have been all but outlawed due to the need for energy efficiency. And dimming of fluorescent lights was first impossible, then possible but expensive, limited and problematic. Four things have changed all that for the better:

1. DALI - the Digital Addressable Lighting Interface - an open protocol and an international standard. This means that you can buy a DALI device - like lights, LED controllers, fan controls, and a growing list of other things - from almost any manufacturer. This allows you to mix and match them together with any DALI-compliant controller and line power supply. But even better than that, every light has sophisticated dimming and scene control built-in. And with DALI every device has its own unique address, and can have its own maximum and minimum levels, power on levels, and much more. Each DALI light or device can also be part of up to 16 different groups.
2. Dimmable fluorescents - Nowadays, fluorescent lamps and compact fluorescent lamps can be dimmed with DALI luminaires (this is not the case with so-called 'retrofit' cfls). And the dimming is 1-100%, flicker free. This means you can have highly energy efficient lighting without making your lounge room look like a factory.
3. Inexpensive controls - The DIDIO from Creative Lighting is a good example of the advent of much cheaper lighting controllers. The DIDIO only weighs around 175grams, but is no lightweight when it comes to features: depending on the firmware it is loaded with, it can have infra red remote controls, pushbutton and motion sensor triggers, supply the DALI line with the required power supply; and provide scene control for up to 12 scenes from just one DIDIO. And a DIDIO's embodied energy is smaller, saving room and energy.
4. Easy programming - Instead of having to pay engineers to write special code to control your lights, with new products like the DIDIO with its patented PAINT programming, you wont be going anywhere near a computer, and you can simply programme different scenes yourself with just a few buttons, making scene control cheaper and easier to implement and change whenever you like.

First start with deciding how to automatically sense that the space is being used so that the lighting will be on when required, and off when nobody is around. The security industry have a very wide range of motion sensors to choose from. We recommend ones that have normally open, voltage free contacts.

Consider the access to the space - can it be accessed from more than one point such as from a door at each end? If access is only from one point, you need only have one sensor covering the entry. If there are two or more entry points, they too should have one or more sensors. Once you have sensors selected, you only need to decide how many DALI lights need to be used in the space - a job best done by a qualified lighting designer or engineer.

As an example, we have a store that is about 6m long and 4m wide with three entry points - one at one end and two at the other - and it is lit with 3 suspended DALI twin fluorescent luminaires. Because we know there are three lights, and we have installed a sensor to cover each end, we have programmed our DIDIO to not only fade up the lights when motion is sensed, but to also bring up the lights in the direction of travel through the space. That is, the light closest to the sensor which tripped fades up, then the centre light, then the light furthest along. Which looks pretty cool! When no sensor is tripped for 5 minutes, the lights fade down slowly to a low level and after another minute they turn off. If someone walks in when the lights are low, they immediately fade back up again and if the lights were off, they fade up sequentially again, repeating the process automatically.

The Riverside Parklands (pictured) has a series of interconnecting boardwalks along the mangroves at the water's edge. These boardwalks constrain visitors to certain paths and create an opportunity which can also be applied to other footpaths. Rather than have the lighting burning away at full intensity when nobody was on a given section we reasoned that we could use beam sensors, diguised as lights (albeit vandal and weatherproof), to sense people. With the ability to sense people reliably, we then need only have a control system that would hold lights low until occupancy was sensed, then fade them up for more than enough time to allow the pedestrian to pass through to the next section of boardwalk (or leave).

What happens if you decide to stop and admire the view? In that case, the lighting will fade down but not off, allowing your eyes to dark-adapt and enjoy the stars with less foreground illumination. If someone else then approaches you by joining you on that section of boardwalk, the system will warn you by automatically fading up again, which also provides you with more light to enable you to see them better from a distance.

These are the lamps that are in widespread use, particularly in downlights and spots, and most are 50watt 12 volt. Fortunately, the big lamp manufacturers have spent inordinate amounts of money on r&d. Creative stock and recommend Osram IRC lamps (there are other brands and of course you can purchase them from your favourite supplier or from us) which are at least 30% more efficient while offering longer rated life (eg 5000 hours). So a 35w IRC lamp will directly replace a 50watt lamp, reducing your carbon footprint by 30% for every lamp you change. So why wouldn't you? The fact is that these lamps cost more to buy than cheap inefficient 50 watt lamps that may or may not last the same distance as these energy efficient alternatives, but its worth it to change to the more efficient new technology.

These are the stick-like lamps that are in widespread use in wall mounted uplights and those floods people put in their backyards. They are commonly 240volt 500 watt or 300 watt though some are 200 watt and smaller.  Fortunately, the big lamp manufacturers have done quite a bit of r&d on these lamps too. Creative stock and recommend Osram ES (energy saving) lamps which are at least 20% more efficient while offering equal rated life. So a 400w lamp will directly replace a 500watt lamp, and a 230w will directly replace a 300w lamp, reducing your carbon footprint by 20% for every lamp you change. So why wouldn't you? The fact is that these lamps cost more to buy than cheaper less efficient lamps that may or may not last the same distance as these energy efficient alternatives. Note that QI lamps typically are not designed for universal burning and any more than 5% off horizontal can reduce lamp life dramatically.

Choosing the best light for a given task or aesthetic (or both) is best handled by a Lighting Designer/Engineer. However there are a couple of general observations that can be made about this and whilst they are derived from many years working in lighting, they are mostly common sense.

Firstly, if you buy a retrofit cfl (compact fluorescent lamp) to replace your old incandescent lamp, no matter how good the new lamp is (and many aren't), you will have to throw out the electronics that are inside the lamp every time the new lamp dies. The alternative is to change the whole light fitting to one with separate control gear (i.e., not inside the lamp) which means that when the lamp dies, you don't throw out the electronics (and all the energy that went into making those electronics). The downside is the cost of the new light and the cost to install it. The upside is that the new light will probably do a much better job, replacement lamps may be cheaper and longer life, and it will probably use even less energy than a retrofit lamp ever could. Why? Because a light is much more than just a lamp. In a properly designed light fitting the amount of useful light is what's important. Reflectors, diffusers and other light modifiers all play a role and light fitting manufacturers are continually improving their lights.

Secondly, fluorescent lights have evolved. They can now be dimmed. They can be dimmed without flicker. In the case of most T5 lamps, they can dim down to just 1% (3% in the case of compact fluorescent lamps). AND they should be dimmed because a light at 100% is rarely at the perfect intensity and dimming saves energy.

New fluorescents can also run at high frequency, start instantly (no flashing) and more importantly, if they are DALI, they can store scenes, be part of groups with other lights, and much more. They are also long life. New T5s will shortly be upgraded from 25,000 hours to a whopping 40,000 hours. All you need to do, if you plan on dimming them, is run them in for 100 hours (when you first use them, for the first 100 hours of use you should not dim them). That said, fluorescent lighting is not generally suitable for accent lighting. There you need a focussed cone of light, and that means dichroics or the new generation of dimmable leds.

We have achieved this result by:

• replacing all dichroic 50w lamps with IRC 35w lamps.
• replacing all transformers for dichroic lights with DALI transformers.
• replacing standard switching and dimmers with DIDIO DALI scene controllers.
• installing sensors to most offices and corridors and connecting the sensors to the DIDIOs.
• programming the DIDIOs to 'time-out' the lighting after no sensor activity for more than a few minutes.
• replacing some standard lights with DALI compact fluorescent dimmable lights.
• setting air-conditioning in summer to be not less than 25 deg C. We also wear less clothing in summer and don't run the air-conditioning unless it is too uncomfortable.

What else do we do to minimise our harm to the planet?

• We buy carbon offsets for all work air travel.
• We do not use a hot water system at all. We heat only as much water as we need for a cup of tea or coffee and only when we need it.
• We use very little water, replaced toilets with dual flush that use far less water than old types. And we have only the smallest water main into the property. Our total water consumption is an average of 12.23 litres per person per day.
• We separate our rubbish into recyclables for the recycle bin and non-recyclables for the waste bin.
• We store and re-use packaging.
• We design products that minimise energy consumption for others.