## How can I calculate ROI on LED lighting for sports fields, compared to metal halide?

Whilst we don’t envisage having to answer this question in 3 or 4 years’ time, it still often comes up at the moment – What is the Return on Investment for installing LED lighting?  However, to answer this we have to go a lot more deeply into the application of the lighting, rather than just what we are replacing.

Broadly speaking, in comparing LED to LED there are typically two ways of driving LED’s – for effectiveness (maximum light output) or for efficiency (maximum lumens/watt).  When running LED’s for effectiveness, you are driving them hard to get as much light as possible from as small an area as possible.  This typically reduces the size and weight of the heat sink and the number of LED’s.  In this scenario a 5W LED may be operated at 5W. Whilst this gives the maximum light output per cm2, the LED’s are not running very efficiently from an electricity-usage perspective.  This is due to the fact that LED’s lose efficiency as they get nearer their maximum output.  Therefore a 5W LED running at 1W may well be twice as efficient in terms of lumens/watt, compared to the same LED running at 5W.  This means that to have a lamp designed for efficiency means more LED’s, bigger surface area, more weight and, obviously, more cost.

The other comparison factor would from metal halide to LED.  A well designed metal halide fitting like the Phillips MVP is a very efficient module in terms of lumens per watt.  When new, a traditional 2kW metal halide needs a minimum of 1600-1700W of LED to come close.  For a LED fitting this size it means that the LED could well be double the price of the MH units.  Multiply this by 24, 48 or whatever is required for your lux levels, and this could be a significant amount of money.

So, when we come to the question of ROI we have to look at the application.  In a warehouse with dozens of high bays which are running 24 hours/day, the criteria are very different to a sports pitch which is only used a few hours a week.  In the warehouse there is no airflow, the lights are on for long periods of time and are often inaccessible.  Running 100 x 150W lamps for 24 hours a day, 365 days of the year equates to 360kW/day, or 131mW (million watts) per year.  By comparison, a football club using the field for training a few times a week would use around 10mW/year.  The club therefore should be more concerned about the cost of the fittings and the poles.  If a club were to spend an extra \$20000 on a more ‘energy efficient’ system due to increase in luminaire weight and the consequent pole strength, it would take a long to time to get the value back.

This brings us back to the ROI question for sports fields.  As seen in the above examples sports lights are designed around output rather than efficiency due to the short time they operate in a year.  ROI therefore has to be calculated on the cost over the whole life of the project.  In this way efficiency or ‘use of electricity’ becomes much less important and maintenance and hassle factor takes over.  Whilst metal halide fittings perform extremely well and are cost-effective to buy and run, they don’t operate at peak performance for very long – typically around 400 hours.  This means that after 400 hours the output is nearing about 75% of what it was at new.  The bulbs then turn from orange to pink and finally stop working.  Although the actual cost of the bulbs is not that high, bulbs for some older fittings are more and more hard to find and certain models are no longer made.  Having said that, for those that can get bulbs, the bulb is the cheap part – fitting them becomes expensive.  The costs would include the electrician and some form of high lift apparatus.  For many rural towns a boom lift to 30m may be many kilometres away, adding to the cost significantly.  This can result in bulb replacements costing over \$5000/year, even if they are batched together.  Over a 10 year period this significantly increases the cost of what looked like a really inexpensive option.  By contrast, LED fitting typically come with a minimum of 5 year warranty.  If the contract is locked down well, most (reputable) companies offer the warranty to cover parts and labour, including high-lift equipment.  This means that there is an average saving of \$25000 for the first 5 years, even for a relatively small club.

## Conclusion

Don’t take the face value of the raw dollars comparison of metal halide versus LED.  Do the calculations carefully and make sure there is still an advantage after 10 years.  The other risk factor is many metal halide suppliers have stopped manufacture of their fittings so spare parts like ballasts and bulbs may not even be available in 10 years.  This may result in you having to buy spares and keep them in stock which further adds to the costs.  Add the extra hassle of delayed start-up of metal halide and LED looks more and more attractive.  As said at the beginning, we certainly don’t expect to be having this discussion by 2023 but for the moment, metal halide is still just hanging in there.

You’ve proved to be an awesome light over the years’ metal halide, but with LED’s advances in the last 12 months, your days are nearly done.

## Why are LED lights heavier than Metal Halide or Halogen fittings?

To understand why LED lights are heavier than traditional high pressure sodium (HPS) or metal halide fittings we have to look into the way these sources create their light.  Traditional forms of lighting used one of two standard forms of generating the light – Incandescent or HID. Whilst HID lamps are not regarded as ‘efficient’ from an energy usage point of view, when it comes to big field or sport applications they are hard to beat.  Whilst many smaller work light applications had long since migrated to LED, sports fields hung on to the HID’s for one simple reason – LED did not work very well.  However, by 2018 the LED’s had advanced enough to be a serious contender but it still required a lot of heat sinking and surface area to cope with the heat generated from 1500W of hard-working LED’s.

## Incandescent

An incandescent light bulb, incandescent lamp or incandescent light globe is an electric light with a wire filament heated until it glows. The filament is enclosed in a bulb to protect the filament from oxidation. Current is supplied to the filament by terminals or wires embedded in the glass. Wikipedia

Incandescent lamps use a filament which is essentially a resistor.  The electricity passes through the filament and due to the increased resistance the wire gets very hot and glows.  If this was in the open air the filament would oxidise and quickly burn up.  However, the bulb is a vacuum which just allows the filament to glow brightly, creating the light.

## HID

High-intensity discharge lamps are a type of electrical gas-discharge lamp which produces light by means of an electric arc between tungsten electrodes housed inside a translucent or transparent fused quartz or fused alumina arc tube. Wikipedia

By contrast, HID bulbs are filled with gas.  When the lamp is turned on the bulb causes an arc within the bulb, fluorescing the gas which in turn generates light.  Both of these forms of lighting generate heat, incandescent significantly more than HID.  This heat is generated forwards, or through the front lens.  If you hold your hand in front of a halogen lamp you can feel the heat generated.  This means that the protective screen on the front of these lamps needs to be a heat resistant material, often glass.  This not only gives good transparency but also can stand up to the heat.  The most important part therefore was allowing heat to escape from the front.  The main body of the lamp was just thin galvanised plate capable of holding the electronic ballast, bracket etc.  This could be quite aerodynamic as it was filling no purpose other than protecting the internals from rain and dusty.

## LED

A light-emitting diode is a semiconductor light source that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. Wikipedia

Compared to these traditional forms of lighting LEDs work in a very different way.  When an LED is turned on, light is emitted from the front but all the heat goes back down into the PC board.  Overheating of LED’s causing very rapid failure therefore that heat has to either be controlled or removed.  This results in the use of ‘heat sinks’ as a way of removing the heat and dissipating it away from the temperature-sensitive LED’s.  The higher the wattage of the lamp, the more heat sinking is required and the larger and heavier the lamp becomes.  Static LED lamps generate significant heat and with very hot evenings being common, nothing can be left to chance.  A light breeze reduces the heat dramatically but this cannot always be relied on.  There is also the possibility that the lights may inadvertently be left on during the day.  All these factors have to be considered in the initial housing design of the lamps.

The material of choice so far has been aluminium.  It has very good heat transfer properties, is reasonably priced and much lighter than most other metals.  The other major factor it is easy to extrude, mould or shape to whatever is needed for a specific lamp with extruding and die-casting being the most common methods. Other material options have been toyed with over the years, like graphene, along with other polymers, however the heat sink-to-weight ratio doesn’t justify moving away from aluminium in the foreseeable future for high power LED’s like those used in sport applications. So, in conclusion, there doesn’t seem any short term answer to this issue of seemingly over-heavy LED lights.  For the next few years at least we will be constrained in what we can do by way of retro-fitting metal halide or sodium vapour lights based on the weight and sail area.  However, don’t overlook this possibility completely as if you get an engineers report its likely there is some tolerance there which just may be enough to allow for the LED upgrade your club has been longing for for many years.

## Can I use my existing poles to replace metal halide fittings with LED lighting on a sports field?

The question we often get asked is ‘Can I replace my old metal halide fittings with LED but still use my existing poles?’  Although this question is often asked there is no straight answer, apart from ‘Possibly’.  The attractive idea behind this is that the poles generally cost 20% of the total project value and therefore significant savings can be made reusing them.  Additionally, with a 14+ week lead time for the poles, the job could be completed a lot sooner with a lot less hassle and mess.  The savings to your maintenance budget will also be very attractive in the long run.

## The major factors which influence the decision are:

1. Do you even know who manufactured the poles?
2. If so, what specification were the original poles designed too?
3. What physical state are the poles in now?  i.e. rust, leaning over etc
4. Has an engineer certified them?
5. What are the ground conditions and has anything changed since the original install?

Whilst your poles may have happily supported metal halide fittings for many years, LED fittings tend to be around 50% heavier than equivalent metal halides.  Additionally many LED’s are mounted up at an angle rather than flat mount like most metal halides.  This extra ‘sail area’ is a major factor to be taken into account in the engineering calculations and would be the primary cause of issues, even more so than the weight.

A side note on timber poles would be that most engineers won’t consider certifying them.  Therefore the only option would be to replace modules directly with no additional weight or sail area.  This will inevitably result in reducing lux levels but this may not be an issue when compared with the hassle of changing bulbs which are increasingly hard to find.

The issue around over-stressing poles is a real one and mustn’t be ignored or taken lightly.  We know of clubs who have installed extra lighting themselves without professional input and it resulted in 30m poles falling to the ground.  In all these instances no-one was near at the time and therefore no-one was hurt, however the results could have been disastrous!  Definitely not a risk worth taking.

With all that being said, there are some general guidelines which will give you an idea of the safety of a direct swap out:

1. Know what fittings you currently have installed and at what angle they are installed. This allows you (or a contractor/supplier) to calculate the sail area in relation to the weight. Ideally have a copy of the original installation plan.
2. If the new installation is going to increase the weight or the sail area, go back to the pole manufacturer to check if the poles can cope with the extra drag
3. If this information is not known, or not available, get an engineer to assess the poles. There are specialist who will be able to professionally assess this information.
4. Research lighting suppliers thoroughly and find modules that:
a) Mount horizontal (or almost horizontal)
b) Have reasonable weight compared to your existing fittings.
c) Have drivers that are mounted remotely (reduce weight further)
d) Ideally the system runs the drivers in parallel so you only have one pair of heavy power cables going up the pole

Some installation are so old that a lot of this information is not available.  Therefore another option would be to play safe and see if you can reduce the existing light levels.  What are the light (lux) levels and what do they need to be in order to comply with common sense function or regulation guidelines?  If the lighting designers are innovative they can also reduce the height of mounting (and therefore all other pole-stress factors), use less-heavy fittings and still improve light levels.  Do however be aware that reduced height often increases tilt of the lights and therefore may have an influence on glare and spill light.  All these are factors to consider but can generally be overcome by thinking laterally.

## Conclusion

So in summary, if your facility is looking for a way to save money, reusing poles is definitely an option.  However, do the hard work and make sure all the bases are covered.  The hard work is nothing compared with the hard work of dealing with a 30m pole that has fallen over with 200kg of lighting attached!  Having said all that, once you have gone through the pain, you will be more than compensated by the reduction in your expenses budget over the coming years.  Just think of never having to worry about replacement of orange/pink metal halide lamps again (arranging the boom, the electrician, the expenses budget etc!) and it gives you the incentive to push through.

## 5 Ways LED Sport Lighting can Save 70% Off your Power & Maintenance Bill and Generate Income

Replacing halogen and metal halide bulbs and fittings with LED has been the obvious thing to do for the past 15 years.  Well, let’s say 8 years (the promises have been there for 15 but they really haven’t stacked up).

Most of what was said was true – the lamps used less power, required less maintenance and lasted ‘a lot longer’.  Unfortunately, the original claims of 50,000 hours seldom, if ever, proved to be true and many people got burned with sub-standard product that cost 5 times as much as traditional bulbs yet barely out lasted them.

Thankfully, however, the technology improved, and we started to get nearer to the life spans we had been promised.  All these problems did cause people to be more sceptical of wild promises and slowed the progress in some sectors.  Governments then started offering incentives and kick-started a wave of replacements which really got the momentum going in the market.

One of the industries that has been lagging behind (for very good reasons) in all this progress is sport.  Sport fields and stadiums, tennis courts, horse racing tracks and many others have struggled to see the value when weighing up against the potential down-sides of early-life failures.  With a number of companies working on this problem for the past few years, we can finally say that LED has arrived for sports applications, as a credible and genuine alternative to metal halide.

The key benefits are as follows:

## Digital Control and Pay to Play

By incorporating digital lighting into your club you can increase the simplicity of another revenue stream – pay to play.

Apps are available to work in with a number of lighting systems which allows users to book and pay for a court or pitch on-line and turns the lights on at a specific light level for a specific time.

This gives total control to the club and needs no on-site management as it can be done completely remotely. Having this remote control gives you the option to open up availability to non-members for added revenue and attract potential new members.

## Dimmable

With LED being ‘digital’ there is much more control over the amount of light you use. Different lighting levels can be set based on the requirements of the night i.e. training vs competition.

The lighting requirements for a given sport e.g. football, are 100 lux for training and 250 lux for a match.  This means that for any time that match-lighting is not required, a huge saving is able to be made to the electricity usage.

Whilst this was possible with metal halide systems, it meant turning off certain lights and keeping others on, resulting in uneven deterioration of the lighting. Digital dimming can even be done from a phone for maximum flexibility.

## Reduces Electrical Usage

With certain (not all) modern LED sport fittings, energy consumption can be reduced by 40-50%.  This is a combination of high efficiency LED’s and drivers, but more importantly high efficiency optics.

The optics control where the light goes and therefore is very important to overall ‘system efficiency’.  Many lights claim high lumen/watt ratios.  This is meaningless unless you have proved this with guaranteed lux levels on the ground.

This factor, in conjunction with the dimmable feature, significantly reduces the overall power usage.

## Reduces Maintenance

One of the huge advantages of LED modules is low maintenance.

Typically, a metal halide lamp will deteriorate to 75% within 500 hours.  For a well-frequented club, this may be only a few months usage, resulting in either under-performing lights or high maintenance bills.

The lamps themselves are not overly expensive, but often the required equipment (scissor lifts or booms) are very costly – especially in rural areas where they may have to be obtained from many kilometres away.

By contrast, LED’s should operate at a high efficiency for 50 000 hours, only requiring occasional cleaning of the optics.  When assessing the costs, this needs to be factored in.

## Instant On

Having the lights up to full power instantly removes the need for lengthy start up periods. LED lighting is on instantly and if there is a power failure, will re-start immediately once the power is back on.

The added benefit to this is that players appreciate the convenience and get used to having uninterrupted play, rather than the frustration of lights turning off during a game and waiting 20 minutes for them to re-start.

Ultimately this equates to improved turnouts at games, more willing pay-to-play participants, and overall a better image for the club.

So in summary, whilst LED has had a rocky start to their big-field career, we do believe they have finally arrived for good.  The value can be proved, the technology is stable and you can set your club apart, attract new members andreduce your running expenses – all by having digital lighting.

### A Word of Warning….

These benefits are still only true if you have the right lighting partner.  Do your research and make sure that what you are getting does stack up as there are still plenty of old-technology LED systems out there.

If you’d like to talk to one of our expert lighting specialists for advice on upgrading from halide to LED, contact us at Legacy Sports Lighting for a detailed consultation.

## 5 Things to Know when Replacing Metal Halide Lights with LED

The decade-long promise for LED has been ‘longer life and lower running expenses’. Whilst this has proved true in many industries, it certainly is not a given in sport applications.

2kW metal halide fittings have been the industry standard for longer than anyone can remember. Loved by designers for the fantastic light distribution, hated by facilities managers who are forever having to hire a cherry-picker in order to change yellowing bulbs.

LED certainly seemed like the answer until lighting designers complained about substandard light distribution, heavier fittings and uncertain lifespans. Unfortunately, they were right to be cynical as LED has certainly not achieved any notable success in the sport market until very recently.

So, you are now going out to find the perfect replacement for your ageing 2kW Metal Halides.

What do you look for and how do you know a ‘lemon’ if you see one?

Sadly, this is not always obvious and manufacturers certainly don’t promote their weaknesses so here’s a few tips to keep you on the right side of your clubs treasurer and sports captain.

## If Keeping your Old Poles, Ensure you Match Weight and Sail Area

Generally speaking, LED fittings are much heavier than Metal Halides.

The traditional fittings are often big, but relatively light and so the poles were engineered accordingly.  Replacing 20kg lights with 30kg lights may not seem like a big deal, however, when multiplied by 6 or 8, the results can be disastrous, as some clubs can testify!

Poles falling over due to weight overload is not uncommon and can be fatal.

Sail area relates to wind resistance.  Many of the traditional fittings mounted flat or horizontal, giving a small sail area.

Ideally find an LED that mounts horizontal too, as this removes another of the potential issues with overstressed poles when the wind gets up.

## Check Out the Beam Pattern

For all their old age, many of the 2kW metal halide fittings (particularly Phillips MVP) have exceptional beam patterns and are really efficient.

Do not assume that any LED fitting will be able to replace these old warriors easily!

Get a lighting plan done by the supplier or wholesaler and make sure you will achieve ‘equal to/or better than’ results with the same or less kilowatts.

Again, I cannot overstate, this is not a foregone conclusion and if you are basing your decision on energy savings, you may be disappointed.

## Get a ‘Guaranteed’ Lighting Plan

Many companies are willing to provide a lighting plan prior to purchase.

Ensure that you get some performance guarantee to make sure the results are based on sound IES files.

Many IES files are generated using optimum conditions and performance of the light and don’t accurately reflect the performance in the field.

A relatively small error can result in really poor performance on the ground if all negative factors combine.

In some cases council grants are subject to the facility conforming to national standards (i.e. European, Australian etc).  Non-compliance in this case could result in a grant not being given, or even withdrawn.

Not only do you not have a compliant facility, but you have lost funding too.

## Look Closely at Spill Lighting Control

Any aspect of metal halide lighting was good cut off and control of spill lighting.

Many LED’s shine at 180 D and rely on the optic or reflector to control the beam.  This is good, provided the optic is good.

A poor optic will put light where you don’t need it, but worse still, put light where you really don’t want it i.e. in the neighbour’s yard.

The lighting plan should include spill light calculations so that you can verify that they comply with council requirements.

## Make Sure the Lamp Mounts Horizontally

A number of the old metal halides had mastered horizontal mounting.  This reduces sail area as previously mentioned, as well as spill light, and is much better for neighbours and players alike.

Lamps that mount at a 45-degree angle not only waste light, they cause real issues with lighting control.

A well designed light should not need to be angled up by more than 15% off horizontal. If it does, you poles may not be high enough or the lamp itself may not be quite as good as claimed.

## Conclusion

So, the summary conclusion is there are LED lights out there that can do what you need them to do, but make sure you’ve done the research as there is certainly more ways of getting it wrong than getting it right.

Don’t ever assume that LED is better just because it’s LED.  Metal halides are great lights and proved very worthy competitors to their digital replacements.

If you’d like to find out more on replacing metal halide lights with LED, send us an email or give us a call on +61 3 8566 6146 and chat to one of our friendly consultants.

## What Do I Need to Consider When Upgrading to LED Sport Lighting

There are many factors to consider when choosing the an upgrade for your sporting facility: Be it surfaces or stadium seating, there are a myriad number of options available & sports lighting is no exception.

So how does Legacy’s range of LED Sport Lighting measure up when compared to traditional metal halide lights?

## 1-For-1 Replacement of Metal Halide

The Legacy system has been purposely designed to offer direct one-for-one replacement for 2kW Metal Halide modules.  This not only is for the light output but weight and sail area too, ensuring existing poles can be used, avoiding expensive upgrades to poles and power.

## Superior Definition

Whether you’re a small local outfit or a professional club, there are options from 70 to 90 CRI ensure you have the appropriate visibility and definition.

Whilst Metal Halide lamps have a good CRI when new, they start deteriorating within the first 100 hours of use and within 250 hours are only operating at 75% efficiency.

Unlike these traditional lighting systems, LED’s have maintain their performance over an extended period, typically 50000 hours.  This guarantees that the light is operating at a high level throughout the life of the fittings.

## App-Based Control & Feedback

By utilising the Legacy app you can gain remote control of lighting levels or reports on power usage, helping you to optimise the use of the lights.

Other options include charging for usage outside of normal club hours and timers for remote settings.

## 40% Less Power Consumption

By replacing 2kW metal Halide fittings with 1.2kW LED modules, power consumption is reduced by 40% immediately.

Additionally, due to the rapid deterioration of MH lamps, savings of nearer 50% should be realised.

Alternately, if you’re looking to upgrade the amount of light on the field this can be done without upgrading your power usage.

## 90% Less Maintenance

One of the key long-term advantages of LED is that there is no required maintenance for 50000 hours, apart from occasional cleaning.  No bulbs to replace annually, no scissor lifts to hire, just high performance lighting all year round

Instant On

With LED lighting there is no warm up period but are instantly operating at full power.  If you have a power interruption, the lights will be back on the moment the electricity is flowing so there are no inconvenient waiting times.

If you’d like to find out more on how LED lighting can enhance your sporting facility, send us an email or give us a call on +61 3 8566 6146 and chat to one of our friendly consultants.

## What is the Return on Investment (ROI) on sports lights?

Ben, an earnest young project manager brings his new idea to the board meeting – replace our ridiculously outdated metal halides for new, singing-and-dancing LED’s.  ‘Everyone is doing it, the whole world is changing to digital LED – it must be the right thing to do!’ Thoroughly researched, he is confident of 100% buy-in from all.  The features are great, the benefits are blatantly obvious. Then, the boss asks the dreaded question ‘That’s all very well but what’s the return on investment (ROI)?’  Ben fumbles around restating the features and benefits for the fourth time.  Opinions are divided and another amazing project get scuttled before leaving the harbour.

The “ROI” question is perfectly fair to ask and not always easy to answer.  So what we’ve attempted to do is give a clear matrix of influencing factors in relation to replacing metal halides with LED lamps.  We have focused on replacing metal halide fittings on a one-for-one basis, although the calculation is still valid for new build, assuming you select an LED fitting that will allow you to use the same pole construction as you would with a metal halide fitting i.e. luminaires are the same size and weight.

The main and obvious influences on ROI are power consumption and maintenance costs.  However, a number of external factors also will impact a decision like this which are more emotional things which everyone will put a different value on.  These are all benefits we take for granted in our homes and businesses but at this early-ish stage of LED development can be easy to overlook in a sporting application when club funds are stretched.  These include carbon footprint responsibility, spill light control to have happier neighbours, the convenience of digital app based control and ‘instant on’.  Basically the convenience and usability we expect in the 21st century which is often hard to put a price on directly.

## Carbon footprint responsibility

There may well be differing views on global warming and how this is impacting our planet and what sort of crises we are generating for future generations.  Whichever end of the scale we are at in this argument, saving electricity has to be a good thing.  In most countries electricity production is stretched and costs are only going to go one way.  Additionally many municipalities offer incentives to use more efficient devices, further enhancing the benefits.

## Happier Neighbours

Spill light not only costs money in wasted energy but also makes for aggravated neighbours.  Having a pay-to-play system is good news for the club who can maximise their investment, but perhaps not such good news for those nearby who don’t like sleeping in simulated daylight.  Many LED systems offer excellent light control due to each LED having an optic.  This allows for very specific focus of the light to go just where it should, dramatically reducing the stray light.

## App based control

Imagine your facilities manager being able to turn the lights off from his bed at 2am when the last rowdy players have forgotten to do so. Better still, set the app so that the lights turn off after a specified time, or when the key-holder leaves, or when the players’ credit has run out etc. etc.  In other words, digital lighting gives us exceptional control of how we manage our lighting to minimise running costs and maximise the clubs ROI.  By making pay-to-play so simple and controllable, clubs can rethink how they make the facility available 24/7, boosting attendances and fees without impacting on their pay-roll.  Additionally, being able to control the intensity of the lights allows you to have different levels of lighting for different sports or levels of play.  This again gives more control of your costs as you can dim the lights to pre-set levels if full power is not required.

## Instant On

Have you ever been frustrated with how long your lights take to warm up?  Or worse still had a match in progress and the electricity has tripped, causing a 20 minute delay while the lights warm up to full power again?  A benefit of LED that is hard to put a value on is the way they power up in seconds.  Even with a soft start they are operating at full power in under 5 seconds.

## Digital Convenience

Like with many things in our modern world there is a convenience about digital which is hard to put a price on.  Ever considered what life would be like without a smartphone? We now can’t even imagine how terrible this would be but smartphones have only been in existence since 2007. Once we have made the commitment to going digital the benefits compound and it becomes very difficult to image how we managed ‘in the old days’.

## Conclusion

So, bearing in mind the somewhat ‘intangible’ benefits mentioned above, put your numbers into the ROI Calculator below and you’ll quickly be able to see how long the investment will take to pay off.

## How do I plan lighting for a domestic tennis court?

Tennis court lighting, like most things in life, vary dramatically depending on the type of usage and personal preferences.  In principle, the ball is small and moves fast.  This usually requires a higher level of lighting than, say, a football.  The important thing to bear in mind is that it is always cheaper to do the job right the first time than to have to redo it in 2 years’ time.  Other factors will include how close are your neighbours and how much do you want to spend.

Lighting levels

This would be the first consideration as everything else will be based on the lux levels required.  For basic play and just to have enough light to see the ball a minimum of 100 lux is required.  This would be suitable for a late night fun game, however, if you are more serious and using the court for training you should really be working to 250 lux.  This will give you sufficient light for higher speeds of play and would be where many good clubs operate their lighting levels.  At the next tier up, competition courts operate at 500 lux.  These lux levels allow for high speed play and would be suitable for any class of player.  Any light levels are achievable, it just depends on where you see your style of play in relation to the budget you set.  To go from 100 lux to 500 lux would require approximately 2.5 times the poles and light modules.

Along with the overall lighting level, uniformity, or evenness of the spread of light is equally important.  It is not sufficient for a designer to quote an average lux level as this could vary from 500 lux directly under the fittings, to 100 lux in centre court.  The average may be 250 but the useableness of the light will be hampered by being patchy and uneven.  You therefore need to ensure that the uniformity factor is round 0.4.

## Light Control

In order to make sure your friendly neighbours stay friendly, check the lighting plan provided by the supplier to ensure there is no spill light at ground level.  Also ensure the lights mount horizontally.  This will tend to be the more specialised lights as many of the cheaper modules will mount at an angle.  Whilst these angled units are less expensive, they can cost a lot in relationships as the glare from these lights can be literally seen for miles.

## Pole Height

For domestic courts this is usually best to be kept as low as possible to minimise glare and over-spill light.  Depending on the light fitting used and the lighting levels required a height of 6m to 8m is usually feasible.  For public areas poles up to 20m are used, particularly when lighting a number of courts from a restricted number of poles.  This height make uniformity easier as the light spreads naturally when given more distance.

To compensate for the lower poles it is often necessary to use more poles.  For instance if using 10-15m poles, 4 would be sufficient to get 250 lux and good coverage.  If 6-8m is ideal then 6 poles may be required to get the same results or 8-10 poles to achieve competition lux levels.

The main problem with metal halides was that when bulbs needed to be changed, the higher the poles the bigger the hassle. With LED’s having now come into their own in terms of reliability and longevity, keeping pole height down to make servicing easier is no longer an issue.

Remember that often these poles, although galvanised to resist rusting, can be powder coated or painted to suit your environment.  Black or white are common but other options are often available on request.

## Pole installation

Lighting poles are now available virtually off-the-shelf from a number of reputable suppliers.  They conform to relevant regulations and the manufacturers can provide drawings and specifications to help aid a council planning submission.  The poles are mostly supplied with a complete installation kit including a frame structure which gets concreted into the ground.  This, along with the installation instructions, makes it simple and safe for any good contractor to install the poles.

## Electrical requirements

The typical current draw for a tennis court will be from 2.4kW (less than a kettle to boil water) for achieving 100+ lux up to 6kW which would provide competition level lighting with 10 poles.  The modules typically are supplied with an LED driver which can be mounted at the base of the pole or may be integrated into the design of the lamp.  Whilst the wiring up and installation is simple, ensure that a qualified electrician does the installation and that the modules are compliant with local regulations.

## Conclusion

This planning work will put you in good stead to have a lot of fun for many years to come.  A cautionary note would be to use this guide to cross check what you are told by contractors.  Sometimes things that are simpler, easier and cheaper for them may not be best for you in the long term.

Good luck and enjoy the game!

## Converting metal halides to LED by replacing bulbs

We often get asked the question ‘Can I replace metal halide bulbs with LED bulbs in the same fitting?’ Whilst this would be nice and convenient it is unfortunately not possible at present.  That is not to say it will never be possible.  As most of us over-30-year-olds can testify, things that were totally impossible are suddenly and surprisingly ubiquitous the next minute.  For those under 30 nothing is any longer regarded as impossible, so watch this space!

Although all lamps generate heat in some form or another, the way metal halide and other traditional forms of lighting work is very different to LED.  Metal halide lamps push their heat forward.  This means that they need a glass or high-temperature plastic cover to cope with the heat.  However, the body or frame holding the bulb itself can be light and thin, often mild steel or plastic as there is no heat coming out the back of the lamp.  By contrast LED’s generate a lot of heat but it flows out the back, with very little coming forward.  In this way a plastic lens can be used for the front, but requires an aluminium heatsink as the back part of the housing to help remove the heat build-up.  This simple contrast means that (for the moment) the way the 2 types of lamps operate is fundamentally too different to be able to make the change simply by replacing bulbs.

Whilst we are aware there are products on the market which claim to do this swap out, be very careful.  At this point a realistic wattage replacement is 1.2kW of LED for a 2kW of metal halide power.  As of mid-2018 this would be regarded as a highly efficient sports light.  This means that the heat generated is equivalent to 240 x 5W domestic lamps, but crammed into a light that is about 600 x 600mm.  If you were to further reduce this size to that of a 2kW bulb, it is technically, and practically, impossible to remove the heat.  As a build-up of heat would destroy the LED’s, this leaves the only other conclusion that it cannot therefore produce the right amount of energy. This is of course simple to prove.  Get lux readings of your existing lighting layout and then ask the supplier of the alternative bulbs to do the same.  If they don’t have the facility to produce lighting layouts it is very unlikely that the product will work.  If they can prove that it works then you know that science has again progressed and we need to do some catching up.

The response is often ‘Well it works at home!’  This is perfectly true and is only possible due to the low current draw of these lamps and, consequently, the low amounts of heat that will be generated.  The more that is expected out of a lamp in terms of light output, the more heat will be generated.  Domestic lamps are often only 3 or 5W but produce a good glow in their setting.  Compared to a high intensity lamp like a sports fitting, these domestic units are very large by comparison, giving a lot of surface area which also helps dissipate heat.  If a sports light was created that used domestic 5W bulbs it would likely measure more than about 2sqm.  Space in the ceiling of house is not really at a premium, hence light fittings don’t have to be very streamlined.  However, having a large and heavy light 25m in the air increases the cost and engineering challenges for the pole manufacturers.  Additionally, if clubs are wanting to replace metal halide fittings with LED, the modules have to be similar to the metal halides in dimensions and weight for the same reason.

The only viable solution currently is to have a module that is matched in size and weight as mentioned, but then also has optimised light output to compare with the metal halide.

So, proceed with caution if the option looks too simple and cheap.  As with most things in life, if it looks too good to be true, it may be just that!

## Are LED fittings more energy efficient than 2kW Metal Halide for sports fields?

If you have looked into LED lighting at all you will have noticed there is dozens, if not hundreds, of options.  So, as you can imagine, there a dozens, if not hundreds, of variations to the answer of this question. They range from 100W to 1500W, big fins, small fins, fan assisted, metal pressed, die cast, white powder coat, black powder coat, COB’s, small chip LED’s, high efficiency LED’s and so on and so on.  Your head begins to spin at the options, but one thing you can be sure of is that LED is the most efficient – right?  Wrong.  Or more correctly – potentially wrong.

Let’s just confirm that point quickly as it is really important – just because it is LED does not mean that it is energy efficient.  Or, conversely, just because it is old technology metal halide does not make it inefficient.  A number of factors need to be assessed to decide if LED is going to work for you.  How often are the lights used, and for how long etc. etc.

So let’s look at some of these factors in a bit more detail…

## How often are the lights used and for how long?

A while back we had a client insisting on looking at LED.  They ran a rodeo once a year for one night and he felt LED was going to give him the best return on investment because if ‘was the best’ and ‘the latest technology’.  Needless to say we were dubious.  The LED fittings he wanted cost 4 times that of metal halide and the amount of electricity used in the year would have only been 10’s of dollars because of only being used once a year.  In this case there was no way of justifying the purchase.  On the other hand, making a 40% energy saving on 100’s of hours of use per year can make it very viable.

## How many lights will I need to use?

The only way to conclusively check if there is a gross energy saving is to get a lighting plan done.  If you are using the existing poles then you can figure out what lighting levels you already have and get a comparative study done using LED.  You can immediately see if you will require more or less fittings and energy by the layout results.  Don’t take this as a given that LED will reduce your energy consumption.  Most systems are less efficient than their traditional alternatives.

## Optics and field size

The larger the field, the more difficult it is for LED to improve on power consumption.  This is because many of the LED optics are not optimised for big field sports and are therefore very inefficient at distributing the light, particularly at a distance.  The critical factor is the control of the light with optics or reflectors as this determines ultimately how many LED watts will be required.  Again, a lighting plan using the IES file for the specified light is the only way to know if it will work or not.  Don’t baulk at this step.  It may cost a few hundred dollars at worst, and at best could save you hundreds of thousands in wasted investment.

To conclude then, efficiency is relative to the size of the investment vs the usage of the lights.  Assuming you get a really good optic and can replace your metal halide fittings and get a 40% saving in electricity, make sure you get a sensible return on investment by looking at the whole lifetime cost, rather than just focusing on the isolated factor of energy consumption.