For maintenance staff, the Outage [when the power plant is shut down for maintenance and repairs which can't be done while it is working] is a short, intense period of work completely unlike the rest of the year. Although our days are dominated with twelve-hour shifts for fourteen days straight, we get to sleep in our own beds and travel a normal commute home.
I've managed to scavenge a Saturday off and end a few shifts early. One of the apprentices explains how he'd wanted to "opt-in" to the EU Working Time directive when he signed his contract, but our line manager had told him “If you want to sign that, there's no job for you here.”
For the visiting contractors this is a different ball game. One of the workers grinding debris from the inside of the furnace tells me he's been moving from outage to outage across the UK, working 10-12 hour shifts, and hasn't had a day off in fifty days. Because every plant wants to do repairs in the summer, when power demand is low, the handful of companies specialised in servicing the machines race around the country during "outage season".
Leeds energy recovery facility, for example, is an exact replica of Sheffield, but their outages overlap. This means that the hydraulics engineers I'm working with have to race up to Leeds at the weekend to begin work they “should have finished” during the week at Sheffield. One of them complains that “My missus is livid about me ditching the caravan holiday.”
Of course, outages often go over schedule. I'm walking out the door one evening when two mechanics run back in and begin rummaging through boxes.
Our team tries clamping the pipe, then welding it, then clamping again, and at 7.30pm the boss tells the fitters to go home. The electricians stay till midnight working on the gas burner signalling problems.
A day later the gas burners are working and the furnace is lit, but the turbine valves are failing. Two systems engineers and two turbine engineers are kept in the switch room overnight trouble-shooting. When I catch up with the system's engineer the following day he's slightly delirious and tripping over his own feet. The turbine guys are remarkably cool and collected in their greasy red overalls – they take a two-hour nap in their cabins, eat some pot-noodle, and get right back to it. “Welcome to engineering.”
Eventually it turns out that the control system is working fine, but the valves themselves are faulty. A part is swapped and the valve begins working well; we "stroke" it to force the air out of the hydraulic oil system, but this causes a pipe burst and hot oil soaks the contractors. Once this is corrected, the turbine fails again.
“It's over-heating,” says the operator “It's 30 degrees outside and the cooling system is failing.”
Our team returns to the cooling system and a brave or stupid electrician takes apart pipes which pump water at 75 degrees into the turbine housing. We watch, alongside my manager, anxiously as he isolates the leg and removes the filter cap, expecting a build-up of pressure to burst out and burn him. Luckily, no-one is hurt. Back in the control room, a manager asks:
“Did you do something in there, because it's working?”
No-one says anything. Finally, finally, the turbine comes online and the responsible engineers are allowed to go home.
• Emma Rickman is an engineering apprentice at a Combined Heat and Power plant in Sheffield.