Keeping the power running: the importance of planned outages for routine maintenance

Just like our household boilers and cars need a regular service, so do our power plants to make sure we keep them running efficiently and reliably throughout the year.

Benjamin Wood is an Electro-Mechanical Engineering Degree Apprentice with the maintenance team at our Blackburn Meadows renewable energy plant in Sheffield, and is well placed to explain what happens and why this work is so important to the efficient running of sites like this – sites that ultimately help to keep the lights on for our homes and businesses.

Blackburn Meadows routinely powers down twice a year for what’s known as a planned outage – like a service and MOT for a car, but many times bigger and involving literally hundreds of people (it also has it’s own language, with some very specific names and tools being called on).

All of this is essential so maintenance and inspections can be carried out – work which isn’t possible while the plant is operating. During winter, the outage is planned to take just a week, with a longer maintenance period during the summer months when energy demand is lower.

So what happens? Much like your home boiler service, the power plant boiler is basically cleaned, but on a much bigger scale. In fact the average domestic boiler can be about 30 kilowatts, compared to Blackburn Meadows which can generate up to 30 megawatts of power – meaning it’s 1,000 times bigger!

So instead of a small brush to clean up, the team relies on small explosions to knock the build-up of rock-like ash deposits off the walls of the boiler so the rock (it’s actually called ‘slag’ but we chose to rename it) can be removed. It’s around 1,000 degrees Celsius inside the boiler when its operating, so this maintenance can only be done when it’s turned off.

During the outage, the maintenance team will maintain or replace any old or worn equipment. This often involves moving large parts of machinery on to the various floors of the boiler house, which takes a lot of careful planning and skill to do safely. An example of this is servicing the bunker screw, one of many pieces of large equipment that move the wood throughout the fuel handling system. At eight metres long and weighing around 1,300kg, this must be lifted carefully over 20 metres to allow inspection and maintenance.

These outages are a crucial part of ensuring the plant continues to operate efficiently throughout the year. To make this happen, more than 100 engineers come together to carry out this essential maintenance, undertaking inspections and any repairs that can’t be done while the plant is operating. Throughout the outage period there is also a focus on site efficiency and safety throughout.

During this winter’s outage at Blackburn Meadows, Benjamin Wood and fellow apprentice Amrit Kuldip captured behind the scenes footage to offer a rare glimpse into the scale and technical expertise involved as the biomass plant prepares for the colder months ahead.

Ben, 21, has been working at E.ON for almost two and a half years as an Electro-Mechanical Engineering Degree Apprentice and is now halfway through his course at the University of Nottingham. Now on his third placement, he already has gained experience working on district heating connections at E.ON’s Citigen energy centre in the City of London as well as on an energy efficiency partnership at the Queen’s Medical Centre in Nottingham.

 “The course has been a fantastic opportunity to gain skills and hands on experience across a variety of sustainable energy projects. I’m really enjoying the course and the scope of experience I am gaining. I’m thoroughly supported both at work and at university. And at the end of the course I will not only have a degree in Electro-Mechanical Engineering but also five years’ work experience.”