All you need to know about lights in farm buildings

Most farms have a variety of lights about the place, many of them in use since Maggie Thatcher was in No 10. That made perfect sense because lightbulb technology had not changed for ages.

But in the past five years, LED technology has massively improved lighting standards, with all the existing technologies suddenly looking very old-fashioned and inefficient.

More than that, we need to look at light bulbs in a different way. The wattage on the side of the cap still gives you a rough idea of the power of the bulb – for instance, 40W or 60W – but a more useful guide to how much power is being used is to look at the lumens. Or, to give them their proper name, lumen/Watt (lm/W).

See also: Boost your gutters and keep your farm buildings dry

What’s a lumen? It’s simply a means of measuring how much light a bulb gives out (which is what you want, of course) and the figure is written on every bulb.

The number of lumens on the side of the bulb actually tells you how much light is seen by the human eye, so is a better indicator of performance than wattage, which simply tells you how much electricity is flowing into the light. If you are choosing one light over another, just compare the lumen figures.

There’s another term you’ll see bandied around called lux. It’s nothing to do with soap powder – it takes into account the area over which the light is spread.

Also, if you’re over 50, you may need to pop a small magnifying glass in the top pocket of your overalls. Otherwise, you won’t be able to see the lumen figure on the bulb.

Lights – the good, bad and ugly


Traditional incandescent light bulbs with tungsten filaments have been around for more than 100 years, but are very inefficient. In fact. only 5% of the power used gets turned into visible light.

Incandecent lights inside a barn

So if you still have a few cobwebby 100W bulbs dangling above a dusty corner of the workshop, get rid of them now – they’re using more power than you realise.


Halogen bulbs use a filament but run at a higher temperature and are a bit more efficient than the tungsten ones (ever burnt your fingertips when taking out one that has just gone phut?).

The EU started phasing them out in 2013 and they are due to disappear altogether this year but you might as well replace them anyway.

Compact fluorescents

Curly-wurly-type compact fluorescents (CFL) use gas in a glass tube that is charged with electricity until it glows and gives off light. They use 70-80% less electricity than an old-style bulb and last up to 10 times longer, so you don’t need to chuck them out yet. However, they are gradually being edged out by LEDs.


Fluorescent tubes (strip lights) have traditionally been a good source of efficient and effective light and are still widely found in most grainstores, workshops and livestock barns. They last a good while but need a new starter every few years, otherwise they flicker annoyingly.

Fluorescent tubes inside a farm workshop

You can still replace an old-school fluorescent tube with a new one but it’s getting harder to find some of the sizes. A new 4ft (1.2m) tube will cost you about £15.

However, it might be better to pay £40 for a 4ft 23W LED or £45 5ft 45W LED for a brighter, more efficient replacement. You never know, it could improve your welding skills altogether.

Yard lights

Sodium lights have been around since the 1930s and come in low and high pressure versions. They are used for mainly for street lighting but are ideal for anywhere around the farm where light is needed all night.

Lights in a farm yard

© Anthea Kitching

What’s the difference between metal halide bulbs and high-pressure sodium ones? They are both part of the HID (high-intensity discharge) family of bulbs, but metal halide bulbs give out a white light while the sodium one is orange. You can’t swap them around, either. 

A high pressure sodium lamp will last for 12,000-24,000 hours, while a metal halide lamp will (on average) last between 10,000 and 15,000 hours. However, the latest LED yard lights will give you more light for your money.

Grainstores and lights

There are still plenty of glass bulbs in grainstores, but ideally they should be changed to LED polycarbonate versions, which can’t shatter.

Want better light levels and less electricity cost? Look for the latest LED light units to cut power usage. A 150-200 lux rating can put up with being on for 18 hours a day.

Lights inside a grainstore

© Tim Scrivener

What’s also good about LED lighting? Milk yields are said to increase by 6% and apparently flies aren’t as attracted to LED lights as conventional ones.

Livestock, lights and moisture

As autumn turns to winter, lights have a harder time coping with higher moisture levels. Also, ammonia from cows can be hard on fittings. That may not be a problem, but if you want to take a belt-and-braces approach, look for the IP rating. IP65 is a good standard but if you want to be really sure go for IP66.

Looking to get a better light in sheds? High-bay LED lights with a 120deg viewing angle are ideal and cattle also like LED lights because they don’t like the flicker of fluorescent lights.

Go for quality LEDs

While there are hundreds of makes of LED lights (and many levels of quality), most farmers would want something that will last. If that’s the case, then go for units that have a higher-quality ballast (the driver that makes the electrodes pulse at each end). Here are a few options:

Kellwood lighting

Offers supply and installation. Its Hamilton and Forsyth series for provide high bay lighting and it also has the higher-output Ayrton Series.


It has high bay lights for buildings, while low bay lights have a wide beam angle for buildings under 5m. They are dimmable, IP66-rated and can cope with wet and dusty applications. Lights come with a polycarbonate cover, no glass and offer a 50,000-hour service life.


IP66 LED waterproof pressure-washable 20W to 80W battens luminaire are dust-proof. You can also have dimming and motion sensors.

Lojer says that work in several universities in the US have shown that increasing light levels to 200 lux in stock housing for 16 hours a day with a CRI (colour rendition index) of 80 can help increase milk production by 6%.


Luxum offers a range lights for livestock and grain stores that replace old-style CFL lights. LED heavy-duty floodlights use Philips Lumileds.

They are waterproof for indoor and outdoor use. Polycarbonate lenses are available for places where a glass lens is not desirable.


Wynnstay’s Enviralight Day-Lighter and Moon-Lighter combines induction and LED lights housed in a robust IP65 (OK for wet locations) fixture and optical lens. Lights can be set for long-day and short-day lighting. Sensors accurately detect when natural light is strong enough to provide adequate lighting levels.

Induction lighting does not have filaments, electrodes or metal caps to seal the ends so it doesn’t have the components that cause florescent lighting to breakdown prematurely. The unit is rated for more than 100,000 hours of life.