In Devon, a public swimming pool is being heated by an unusual source ─ a small, local data centre. Data centre use is ubiquitous, with virtually every business using its own, or someone else’s, data storage system. But power outages continue to pose a problem for these services, which, by the nature of their application, need to be available 24/7.

So how can we minimise the risks? Here, David Atkins, projects director at resistor manufacturer Cressall explains.

Data centres are physical facilities housing an organisation’s IT infrastructure, including its networked computers and data storage. These centres support many aspects of a business’s online applications and activities, whether it’s virtual desktops or enterprise databases. With the accelerating pace of digitalisation, the demand for data services is growing exponentially, with McKinsey and Company forecasting the demand for data centres in the US to grow ten per cent year-on-year until 2030. Similar growth has been forecasted in Europe and the Far and Middle East.

However even with the growth demand, data centres have an increasing problem ─ power outages. According to a 2022 report by the Uptime Institute, 20 per cent of organisations experienced at least one severe outage within the last three years. And more than half of those outages are costing businesses upwards of 100,000 GBP/Euros/USD in losses.

More than 40 per cent of outages that are classed as ‘significant’ in terms of their downtime and financial impact are related to power, with the single biggest cause of power incidents being uninterruptible power supply (UPS) failures. So why are outages such as a big problem with data centres, and what can we do to prevent them?


Data centres are estimated to be responsible for around one per cent of the world’s total electricity usage. Devices and equipment run constantly to ensure an always-available service, consuming energy and generating a lot of heat, which in turn requires an advanced cooling system.

Combined with other common problems, such as machines reaching their end-of-life and equipment failures, means that the maintaining the infrastructure of a data centre is something that needs to be planned and supported. Making them more reliable doesn’t need to be complicated; with the right design, planning, and maintenance testing programs in place, data centres can maximise their efficiency and minimise potential downtime.

Ensuring sufficient infrastructure is in place right from installation helps to ensure that the facility has everything it needs to support its operations. Trying to squeeze in additional equipment at a later stage, though tempting, is only likely to increase the risk of potential problems caused by systems running at overcapacity or overheating the existing cooling systems in place.

It also doesn’t leave any servers free to reroute services to if another one fails, making contingency planning much more difficult. It’s important when making plans for potential failures that all potential problem areas are considered. For example, hot weather can put additional strain on cooling systems, so it’s recommended to leave some allowance for environmental factors.

Plans should also be made in case of blackouts. Data centres rely on the availability of a constant stream of electricity. In the case that this cannot be provided, there must be a working backup generator that can keep operations afloat.


Implementing regular testing programs and inspecting all items of equipment is key in preventing outages and ensuring that all machines are operating correctly. But testing in these environments can be challenging. With many data centres designed to maximise equipment space, there may be limited room for maintenance workers to carry and move large testing equipment.

Furthermore, the testing must be carried out to a level that is representative of its working load. This is particularly relevant when it comes to backup generators, which may be called upon at any moment to provide power.

It may be difficult to find a tester that maintains its portability while being capable of handling the voltages present within data centres, but opting for a more compact solution like Cressall’s EV2 could be the answer.

Frequently implemented in electric vehicles to aid regenerative braking, the EV2 offers a high power-to-weight ratio of 9.3 kW/Kg. Its modular design also means that multiple units can be combined to cope with loads of up to 600 kW per cubicle making it ideal for these environments. The EV2 can also tap into the data centre’s existing liquid cooling system to dissipate the generated test power, meaning no further heat is lost into the air when testing, so putting no further strain on the existing air-cooling systems in place.

With demand for data centres only set to increase, improving their efficiencies and minimising downtime is high on the agenda for operators. And with the right design, planning and testing programs in place, the threat of outages no longer needs to cause alarm.



Mike Torbitt, new Cressall M. D.


Cressall Resistors announces the appointment of Mike Torbitt as the company’s new managing director, from 1 December 2023. With an impressive background in leadership and a wealth of experience in the engineering and manufacturing sectors, Mike brings a dynamic and strategic vision to guide Cressall Resistors through its next phase of growth and innovation.

Mike joined Cressall in December 2021 as head of finance and business systems, and additionally took on the role of deputy managing director in October 2023. He takes over from Simone Bruckner, the outgoing managing director, who’s led the business for over eight years.

Mike has over 17 years’ experience in key finance and leadership roles across a range of industries, including a stint as UK finance director at sporting and outdoor goods manufacturer Thule Group and several roles within the automotive and manufacturing industries.

His successful track record includes spearheading business strategies, driving operational excellence and fostering a collaborative work environment. Mike’s pragmatic leadership and experience as a highly trusted team player is demonstrated through his record of commercial success at several multimillion-pound organisations.

Cressall, with its global footprint and strong reputation for manufacturing excellence, has become a trusted partner for customers seeking reliable and efficient resistor solutions from a range of applications — from automotive to power generation to marine and offshore use cases. Mike’s appointment will allow him to provide strategic consultation and projection with a focus on growing the business’ key areas — its dynamic braking resistor for automotive applications, the EV2, and its load bank division, Power Prove.

“Mike joined the Cressall team almost two years ago, and since then he’s already made a great impact on our operations,” said outgoing managing director, Simone Bruckner. “His strong background in finance and business procedures and proven ability to adopt a strategy of commercial success will ensure the continued growth of the business.”

“Simone has been an ideal role model in the time that I have been with Cressall and I know that he is a tough act to follow,” added Mike Torbitt. “I would like to thank the board of directors and owners for their confidence that I can deliver on their expectations, and to wish Simone every success on his next venture on behalf of the whole Cressall family.

“Cressall has a rich history of delivering high-quality resistor solutions to a diverse range of industries. I am eager to build on this foundation, surrounded by a strong, reliable team of experts that are responsible for the company’s success. Now, it’s about evolving an already well-established business and growing our presence in the most promising sectors.”


power transmission

With the rise of offshore windfarms and international grid links, effectively and efficiently transmitting electricity over long distances is more crucial than ever before.

Simone Bruckner, Managing Director of Cressall, explains the role of high voltage direct current (HVDC) and filter resistors in making long-distance energy transition possible.

The UK has four times more offshore windfarms in operation than in 2012, with the number set to rise significantly as the government looks to reach its goal of generating 50 gigawatts (GW) of offshore wind by 2030.

Along with this rise, international and intercontinental grid links have increased as the UK trades excess power with other countries, much of which is generated by renewable means. Trading the surplus not only saves energy, but also prevents Brits paying to turn off turbines when more energy is generated than the grid can take.

As the UK currently has 13.9GW offshore wind capacity compared to its 50GW goal, it is important that this output is used efficiently and energy loss is kept at a minimum. Although alternating current (AC) is standard in electrical power transmission, the current often concentrates near the conductor’s surface – known as the skin effect – which causes energy loss.


HVDC is a transmission system that uses direct current (DC) for the transfer of power over long distances. As remote offshore windfarms and the grid are often far apart, HVDC enables effective transmission due to its uniform current density throughout the line.

Additionally, HVDC supports the trading of excess power between unsynchronised AC distribution systems, which run at a set frequency and cannot be connected to those with a different frequency. As HVDC does not have a frequency, multiple circuits can be interconnected and converted to both system voltage and frequency levels of the system at point of use.

While HVDC is used for international grid links, it must be converted back to AC at the local grid level. However, converters create harmonic distortion, which in turn can cause lower efficiency, overheating and increased chance of equipment failure.

Therefore, harmonic filter resistors are a vital part of HVDC and SVC converter stations, helping to remove harmonics by dissipating them as heat. This ensures a safe and assured power supply for the UK and countries across the continent.

The UK’s rollout of offshore windfarms currently puts it among world leaders, and with the pipeline of projects close to 100GW, Britain could soon supply many countries with surplus energy. With the ever-increasing need for sustainable energy, HVDC ensures that countries across the world can safely and securely benefit from wind power.


pre-insertion resistors for turbines


Back in 2019, then-Prime Minister Boris Johnson promised 40 GW of UK offshore wind power by 2030. In early 2022, the Government raised that target to 50 GW, with an additional five GW from floating wind turbines. But are floating wind farms the solution to existing offshore power problems?

Many of us will be familiar with the sight of wind turbines. After all, there are more than 10,000 of the structures on land and at sea in the UK. In terms of efficiency, offshore wind turbines often have more favourable wind conditions, producing more electricity per turbine than their onshore counterparts.

But traditional offshore wind turbines have their limitations. Traditional offshore turbines are built onto a large steel column, fixed into a concrete foundation on the seabed. These can only be installed in relatively shallow waters, up to depths of around 60m. Not only does this limit the potential areas for turbine installations, it also means that the turbines have less access to the stronger winds that are often found further out to sea.


To capitalise on the stronger winds further out, floating wind turbines can be built instead. These are turbines built on huge floats, anchored to the seabed with weighted subsea cables.

Operating in much deeper water, floating wind farms make use of vast areas that were previously considered not suitable for offshore wind power. Being further out to sea also means that turbines can be a lot larger in size than their counterparts, producing even more electricity per turbine.

Kincardine, the world’s largest floating wind farm based in Scotland, has five operational floating wind turbines. Three cylindrical floats arranged in a triangular formation support each turbine, and pipes between the floats allow liquid ballast to be pumped around the structure. In this manner, the weight of the turbine can be shifted to stabilise it in harsh conditions, as well as orientating it for the wind direction.