Tag: Drax Power Station

“One of the things I like about my job is working through the challenges we get on a daily basis and finding a solution,” explains Adam Nicholson, Process Performance Section Head at Drax Power Station.

That eagerness to find solutions makes him the ideal candidate for his current job: managing day-to-day improvements at Drax. “I’m responsible for the team which ensures the plant operates at optimum efficiency,” he says. His team make sure the turbines, boiler, emissions, combustion, and mills are not just working, but running as smoothly as possible. It’s a job that brings up constant challenges.

“It’s ultimately what I became an engineer for,” he says, “to follow that problem-solving thirst through.”

Earlier in his career, Nicholson was involved in one of the plant’s biggest problem-solving missions: converting it from running exclusively on coal to also run on compressed wood pellets. It was a unique test – one that required starting from scratch. There wasn’t a bank of existing knowledge that Nicholson and his fellow engineers could call upon.

“We did a lot of testing to learn more about the fuel,” he explains. “We had to understand how to get it to the boiler, how to process it before we put it in, how to convert the mills, and then how exactly the combustion would work.”

Some of that learning involved experimenting with unorthodox solutions to complex problems.

The dog tunnel

“One of the big problems with biomass is you can’t expose it to as high a temperature as you can coal,” Nicholson explains. This presented a challenge when it came to pulverising it.

Before fuel at the power station can be combusted, a set of mills pulverises it into a fine powder using a ring of rotating, heavy-duty balls. This fuel powder is then dried inside the mill with a mix of hot air drawn from the boiler house and cool air. But a fundamental difference between coal and biomass meant this process had to change.

“With coal the air can enter the mills at about 300 degrees. With biomass, if you get much above about 180 degrees, the biomass will set on fire,” says Nicholson. As part of the R&D phase he needed to work out a way to cool the mills down on a temporary basis. “We all took a big gulp and thought, ‘how are we going to do this?’”

Part of the problem was the existing ducts weren’t big enough to deliver enough cool air to the mills to lower their temperature to a safe range. Nicholson improvised a solution. “It was known as the dog tunnel,” he says.

If he could get a temporary, larger air supply to the mills it could provide more cool air and lower the overall temperature, allowing the testing to be conducted. So he found a company that could supply industrial flexible ducting, which he connected to a larger cold air duct and then fed through to a mill to deliver more cool air. As its informal name suggests, the result didn’t look like much, but it worked.

“It didn’t look like a finished solution, but the theory behind it was sound. For occasions like this we had to think, ‘let’s just do it, prove it, and then we can work on a permanent solution.’”

“That’s ultimately what I became an engineer for. To follow that problem-solving thirst through.”

The next challenge

Now the power station is successfully producing more than half of its electricity from biomass, Nicholson’s day-to-day responsibilities lie in ensuring safe operations and driving process efficiencies. To do this he keeps tabs on the combustion process – for example, by using thermal imaging cameras to monitor the inside of the furnace – and tweaks it to get as much energy as possible from the biomass fuel.

But at a site as large and complex as Drax there will always be new engineering challenges that require inventive thinking.

“Often you don’t know how you’re going to do something until you do a bit more work and try and understand the problem,” Nicholson says. “We’re nowhere near the end of our learning curve.”

“It’s like a living animal, is Drax. It will break, it will fail, it will need maintenance,” says Gareth Newton. As a mechanical engineer in one of the power station’s maintenance teams, he’s a man with a closer eye on that animal than most.

And when something does need fixing or improving, it’s his job to make sure it happens. It’s a task that keeps him busy.

On top of the teams

“I’ve got a team servicing the filter fans. I’ve got a team doing a filter change on a biomass unit. Then I’ve got another company doing a pipework replacement on a discharge line for me. Somebody else is doing a service on the belt cleaners,” Newton says, listing half a typical day’s responsibilities. On any given day, he oversees a number of different teams that carry out a variety of maintenance tasks, and more often than not that list is a long one.

He’s a part of the Materials Handling team who deal with all the material arriving and leaving the power station. This includes the biomass and coal fuel coming in, and the ash, gypsum and other byproducts from the generation process going out.

It means he has a hand in the maintenance of almost all parts of the plant, from the compressed wood pellet storage domes to the boiler. With such a broad perspective of such a complex plant, he knows it’s not always the things you expect to fail that need fixing.

Monitoring the machine

“It’s a machine – it’s being used. It’s not a showpiece or something in a museum. It’s real and every now and then it will throw a gear out and stop,” he says. Those failures don’t always happen to a schedule, so when something does go wrong it can be unexpected.

“You might have a £50,000 gearbox sat in the stores ready and waiting to replace a faulty one, but it will be the £10 probe on a conveyer belt you never thought would break that fails and holds the whole system up,” he says. When something like that happens, he adds, it’s not always about having the exact tool that can fix it right there and then, it’s about thinking out of the box.

“The biggest part of this job, and I think it’s one of the biggest parts of heavy industry engineering, is not fixing or modifying things with what you’ve got,” he says. “It’s about using what you haven’t got to try and engineer your way out.”

He continues: “If you haven’t got a tool or part that you need, can you make something new, can you find a way to make it work? Or, do you even need it?”

“It’s like a living animal, is Drax. It will break, it will fail, it will need maintenance.”

Keeping your hands dirty

Newton grew up around engineering. His father ran a salvage yard and precious metals business and would bring back broken bits of machinery for the kids to fix as toys. “I’ve always had dirty hands,” he says.

It’s something that’s stuck with him. Today, even though he now spends a large proportion of his time monitoring jobs at a computer or moving between teams, it’s the practical side of the job that keeps him interested. “The best part of the job is working with your hands.”

And even though the demands of the living animal that is Drax can sometimes keep him on site longer than his working hours, it’s a beast he’s happy to look after.

“It’s a job you either love or hate. If you didn’t enjoy the engineering side you probably wouldn’t like it because there’s a lot of ingenuity and thinking on your feet needed,” he says. “But there are a lot of jobs out there that I wouldn’t want.”

Before Drax Power Station was a part of Andrew Storr’s career, it was a part of his local environment.

“When I was at school in Selby they were building the second half of the station,” he says. “We could see them building the cooling towers out of the classroom windows.”

But it wasn’t until a careers advisor brought an old cine film of the power station into class that he considered working there. “Part of the film was them stripping the turbine and I watched it and thought, ‘I want to do that,’” he says.

Today, Storr does more than strip the turbines, he’s part of the engineering team that oversees them – a job that needs to be taken seriously.

“If the turbine’s off, forget the rest of it: we’re not generating electricity ,” he says. “We’ve got to make sure the turbine and the generator are absolutely as bulletproof as possible because we’ve only got one per unit.”

Considering the conditions each one comes under, this is no easy task. “The turbine shaft weighs 300 tonnes and spins at 3,000 rpm. The high pressure turbine is 165 bar, and temperature-wise, the steam running through it making it spin is 565 degrees centigrade.”

Bulletproof is an understatement. When it comes to carrying out maintenance on a turbine, it’s more than likely you’ll have to visit Storr’s workshop.

Fixing the governor

The workshop hasn’t always been there. It all started fifteen years ago when a piece of equipment broke. It was a turbine governor relay, a  precision hydraulic actuator that keeps the turbine spinning at the right speed. Drax needed a new one.

“They’ve got to be 100% reliable,” Storr explains. “If they lose control of the turbine, it can either come to a grinding halt or speed up too much and self-destruct.”

The team went in search of a replacement, contacting a manufacturer who came back with a sky-high quote. But Storr’s boss at the time had another idea.

He asked whether Storr could reverse engineer a full set of governor relays. “I made the fatal mistake of saying, ‘Yeah!’ So I set off with a few photographs and a handful of sketches,” Storr explains.

What followed were sleepless nights and a lot of grey hair, but in the end he managed to reproduce a full set that cost nearly half of the original quote. Better than that, they worked perfectly.

“Today, they’re on Unit 5, doing the business.”

Building the workshop

Manufacturing the governor relays was a turning point. Storr and the team saw there could be further savings and benefits if they did more manufacturing or refurbishment in-house. They had the staff capable of doing it, they just needed the facilities.

Although there was some initial scepticism from some in the company, Drax armed Storr with a small budget and he set out on building the workshop. That was 15 years ago. Back then, the workshop was designed to only refurbish equipment, but it has since grown. Now they can manufacture, too.

Today, when Drax buys in equipment which is either very expensive or lacking in quality, Storr’s team can modify it, make it fit better, last longer, or improve its efficiency without sending it away from the plant and incurring extra costs.

“We’re reaping the rewards. We’re leagues in front of everyone else in the UK because we’ve got our own manufacturing and machining facility,” Storr says. “We can do all this work on site. We’re not relying on other people.”

The workshop has given Drax an edge when it comes to its engineering ability, but Storr remains modest about the achievement.

“The thing is,” he says, “I’ve got a good boss and he will support you. But I do see it as a bit of a feather in my cap.”

A station like Drax doesn’t run itself. Its six turbines generate nearly 4,000MW of power when operating at full load. Unsurprisingly, for a site that produces 7% of Britain’s electricity needs, the role of an electrical engineer is an important one – both when managing how power is connected to the high-voltage electricity transmission grid, and how the giant electrical machines generating the energy work.

“It doesn’t get much bigger than Drax. You need to be at the top of your game, every day,” says Lead Engineer Gary Preece.

A man at the top of his game is a fair way to describe Preece. He has been an electrical engineer almost his entire life. Beginning as an apprentice working at the Liverpool dockyards at age 16, Preece has worked a range of increasingly demanding projects and roles, including engineering consultancy and work for the Royal Navy on their Type 26 Global Combat Ship, where he was in charge of designing the on-board power infrastructure.

He became a member of the Drax team five years ago.

Life on the job

“On a station the size of Drax, you don’t have a typical day. There are just too many systems that can change status, that can fail, or that require immediate attention to remain operational. It’s never-ending,” Preece says.

Working as an electrical engineer in a plant the size of Drax doesn’t just mean getting called down to help out when a fuse blows. His responsibilities as lead engineer encompass a broad range of functions.

“There’s lots to do. There’s a lot of hands-on work, but there’s also a lot of study work.” Tasks can include scoping out, planning and budgeting new projects, working with contractors and suppliers, fault analysis and power level studies.

This last role is what Preece has come to like most about the job – working with sophisticated computer simulations to model output and crisis scenarios, all so Drax can operate at its optimal level with National Grid.

“I really enjoy a lot of the theoretical work,” he says. “We can do so much with this software.”

Of course, there are times when he does have to fix things. And in a power plant, mistakes can have major consequences. “The energy levels in a power plant are so high that when something fails, it usually fails spectacularly.”

This means Preece needs to be on call all day and all night. If there’s a technology failure, he needs to be on the site, finding out what went wrong and directing recovery efforts. “There’s no hiding place. If something goes wrong, you have to fix it.”

Transforming Drax’s electric infrastructure

Sometimes individual projects can occupy all aspects of Preece: engineer, thinker and planner.

One of the most challenging was when Drax wanted to import a largely unused industrial generator transformer unit from Kent to the station in Yorkshire.

The transformer was split into three 200-tonne components. Before transit, Preece and his team conducted extensive checks on the components and oil (transformers contain oil to insulate the coil), to evaluate the state of the machinery. And these steps had to be repeated after every stage of the journey, to ensure no damage had been sustained.

After checks were completed, the units needed to be transported via the M25 motorway to ports in the south of England, from which they would travel by ship on the North Sea, ready to be unloaded and transported to Drax for installation.

However, the team hit complications, this time with the Highways Agency. “The structures were so heavy, that we had to take a ferry from a different port because authorities were worried the bridges we were planning on using to get there wouldn’t take the weight of the units. We had to do a turnaround in the middle of the motorway!”

Getting the extra transformers installed gave the plant some important breathing room in the unlikely event of a failure. “Some power stations don’t have spares. If there was a failure, they could be out of commission for months,” says Preece.

For a power station as large as Drax, that would be disastrous. But even with the extra transformers on site, the number of ways the electrical infrastructure at a power plant can go wrong is huge. That’s why experienced engineers like Preece are as indispensable as the machinery itself.

“Drax is one of the best opportunities you’re going to get for artistic licence. It doesn’t get much bigger.”