The majority of farms have varied light around the place, with many of them in use since Garret FitzGerald was Taoiseach. That made perfect sense because the technology in light bulbs had not changed for a long time.
Since 2013, LED technology has improved lighting standards enormously, with all the existing technologies now suddenly looking very old-fashioned and inefficient.
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).
It's simply a means of measuring how much light a light bulb gives out. This is exactly the type of information which you want, and its written on every bulb.
It tells you the amount of light which is visible to the human eye and is therefore a much better indicator than wattage, which only tells you the amount of electricity that's flowing into the light.
Another term that is important to be aware of is the lux. It takes into account the area over which the light is spread.
Traditional incandescent light bulbs with tungsten filaments have been around for more than 100 years, but are very inefficient. Only 5pc of the power used in them gets turned into visible light.
So if you still have a few old 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. The EU started phasing them out in 2013, but you might as well replace them anyway.
Compact fluorescents (CFL) use gas in a glass tube that is charged with electricity until it glows and gives off light. The CFLs use 70-80pc less electricity than an old-style bulb and last up to 10 times longer, so you don't need to throw 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 slatted houses. They last a good while but need a new starter every few years, otherwise they flicker annoyingly.
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 (36Watt) will cost you about €3.50
However, it might be better to pay €7 for a 4ft 14.5W LED or €10 for a 5ft 20W LED for a brighter, more efficient replacement. You never know, it could improve your welding skills altogether.
Sodium lights have been around since the 1930s and they come in low and high pressure versions. They are used mainly for street lighting but are ideal for anywhere around the farm where light is needed all night.
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 last between 10,000 and 15,000 hours. However, the latest LED yard lights will give you more light for your money.
There are still plenty of glass bulbs in grainstores, but ideally they should be changed to LED polycarbonate versions, which can't shatter. If you want better light levels and less electricity cost, you should 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.
During the 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. If you are 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.
Poultry farmers should consider changing the lighting in their sheds to enable their birds to see and perform better.
Poultry vision is very different to humans, not just in colour perception and visual responses, but in physiological responses through hormone changes and behaviour.
Chickens get very little vision from an incandescent light bulb - it looks like a barcode with half the information missing. Combined with its low frequency this causes stress, as the bird is having to use its brain to guess the missing information.
Dust, ammonia and moisture can also get inside the bulb and cause it to fail. Farmers should use bulbs which are completely sealed, and should be used with a symmetry dimmer.
Good lighting should be a priority on every farm and LEDs are of particular benefit. Many pig, poultry and dairy farmers are installing LEDs and the technology is increasing across Europe.
Capital cost is high, but energy savings of 80-90pc over conventional lighting are possible, as well as potential health and productivity benefits.