Energy Savings

I’m no Martin Lewis, I can’t advise on the best tariff, but I understand that one of the biggest costs we have in a print shop, after the squishy things (staff), is energy.

The cost of electric and gas has seen prices increase by as much as 400%.

How can we reduce this necessary cost? The short answer is we can’t. Energy is a necessary part of the process. Renewable energy is a great solution, but if you didn’t put solar panels on the roof last year or you didn’t build a Dutch-style windmill in the car park, then the chances are you are still plugged into the grid and are bound to the ever-increasing prices.

Short of running a giant extension lead to the street lights outside or building your own little Iron Man-style Arc Reactor in the disabled toilet, we can apply a few practical routines to at least reduce the wasted power consumption. This is where I turn into my dad with the occasional phrase like “it’s lit up like Blackpool Illuminations in ’ere.” Common-sense advice such as turning off unnecessary lighting can only go so far.

LED

This technology is rapidly replacing lighting in factories and has also replaced the old metal halide exposure lights that we use to develop screens. The average metal halide is 5000 watts. Add in the power of a vacuum too and we have a huge power drain in the screen room. The average LED is 15 watts. Even Martin Lewis can see the savings here.

Sodium lighting can still be found in some old factories. This lighting was the LED of its time, but the power usage is still high compared to the low-watt LED we see now. It also makes colour matching a gamble that we never win.

Motion detectors in low-traffic areas can add a great saving too. These are like the robot version of my grandad who used to follow my grandma around turning off lights approximately three seconds after she left the room. It was a real gift.

FLASH

The use of flash curers has become similar to a comfort blanket, but these hungry little heat monsters can consume kWh like a toddler consumes the sherbet dips in the pick-and-mix section.

Using higher mesh counts and progressive angles we can reduce the need for that second flash. We can turn down the power consumption on the front of most flash units. A 10% reduction in power output will save in the long run.

If we have the flash running at full power for 3 seconds but we have a double-hit white or a slow delay for shirt placement, then it would be more beneficial to run the power output at 80% for an extra second.

AIR

Here is where I have seen the biggest savings.

An average compressor is 7hp. This consumes huge kW per hour. Often the compressor is running only to feed the air leaks in the factory.

Turn off everything in the factory except the compressor.

Walk through every department, intently listening for the tell-tale hiss of a loose connection or a failed valve.

This might seem like a small thing, but running the all-powerful compressor only to fuel the air leaks in the system is the same as boiling the kettle and pouring the hot water down the drain, only to fill it up and do the same thing again every ten minutes.

Most modern compressors will fuel a receiver tank. This tank will act as a buffer between the machinery and the compressor. When this receiver tank is full and no air is being demanded by the system, the compressor should go into standby. A noticeable drop in the output noise should be obvious. Occasionally the compressor will go completely quiet when no demands are being made on it.

The noisy and hopefully busy environment of a print shop should make it difficult to hear any small leaks, and when we add in the latest playlist from Bob the screen guy, played at ear-shattering volume from the oversized portable speaker that only he has Bluetooth access to, the sound of leaking air is often hidden. It should resemble the noise of 50p pieces hitting the floor every ten minutes.

DRYERS

We need the dryer to cure the ink. There is no other practical way to do this, but we can use new ink technologies to reduce the cure temperature.

I recently used a water-based product that cures at 110 degrees. This is a 30% reduction in heat required, and there are low-cure additives for plastisol inks readily available.

The dryers of old would take an age to reach curing temperature, and some would only achieve this with the assistance of a rogue spray can in the burner. Although this did tend to blow the covers off and increase the medication of poor old Sandra at the end of the dryer, who still has flashbacks of when a flaming green shirt flew past her eyes, singeing her new eyelashes.

Take a time recording of how long it takes the dryer to come from cold to curing temp. Now take a time recording of how long it takes to set up that six-colour job that everyone has avoided for the last two days.

It’s a common misconception that dryers take hours to warm up. Truth is most achieve a good temperature in under 15 minutes.

Breaks and changeovers can often exceed this time, and it’s useful to assign one person as a “dryer monitor,” turning off the heat when no shirts are passing through the tunnel.

REPLACE

New machinery is often more efficient than the old clunky press that eats compressed air at a phenomenal rate.

A new dryer is often more insulated and more efficient at using energy than the one we bought from a guy in Blackpool who listed it on eBay as a used pizza oven.

And a new flash unit to replace that hot-air gun with the trigger held down with brown tape would pay for itself in energy savings alone.

One thing is certain: the energy prices we are paying are very unlikely to come down. If we look back, energy was low on the priority list of endless things to do, but now that it is a huge percentage of our monthly costs, we must look at ways of using this resource as if it is not endless.