A number of measures have been put in place over the years to keep power plant noise levels at an acceptable level and in line with regulations. Now, Wärtsilä and its partners have found a way to increase the quality of life for people who live near power plants while also boosting the plants’ efficiency.
Today more and more people are moving into cities, causing urban areas to grow and spread. With this increase in population comes a surge in demand for energy. And with the share of intermittent renewable energy sources on the rise as well, there are more opportunities for locating flexible power plants near where people live.
However, energy production also, in essence, involves the generation of noise. To address the issue before it becomes – literally – too loud, Wärtsilä and VTT Technical Research Centre of Finland launched a project to create innovative solutions to further reduce noise levels at power plants.
The project, known as SOPEVA, is funded in part by Wärtsilä and partly by Business Finland, a public agency for research funding and international promoter for Finnish industries. The project’s name is an abbreviation from the full Finnish title, which translates to “socially acceptable energy production in varying environments.” SOPEVA is taking place in tandem with a public project known as Anojanssi, headed by Turku University of Applied Sciences, which has been in charge of developing the perceived annoyance quantification methods utilised in SOPEVA.
The goal of the project was to lower noise emissions by developing both equipment and co-operation within the entire subcontractor network.
“The aim of SOPEVA has been to respond to a need before it becomes urgent,” explains Eirik Linde, General Manager, Environment, Wärtsilä Energy Business .“It’s not a technology we could develop on a whim; when customers ask for it, we want to meet their expectations.”
The most notable sources of power plant noises are the cooling radiators, exhaust gas stacks and ducts, combustion air intake, and ventilation, as well as the running of the engines themselves. The management of this noise has significant impacts on the ways nearby areas are affected.
“Traditionally, the exhaust system has been provided with individual components that reduce noise, especially at a certain frequency,” says Antti Hynninen, Senior Scientist at VTT. “Now, we considered the entire acoustic chain from the sound source to the recipient across the hearing zone. We also used the noise cancellation principle, where components attenuate each other based on the phasing of sound. At the same time, the need for insulating materials was reduced, making the components more durable and environmentally sound.”
These technologies can be utilised anywhere, from a busy metropolis to a small and remote island nation. Germany and the south of the UK, including the Channel Islands, are all places with potential for the technology. These regions have strict local regulations requiring that certain levels of noise emission be met before planning permits for new power plants are issued.
A lot can be done with how the building is constructed, but not all of the possible options are practical. For example, building very thick walls to silence the noise would make a power plant project so expensive that it would no longer be a viable option.
After three years, the project team had developed various solutions that reduced noise emissions by 10 to 20 decibels. In practice, this means a smaller noise footprint for a power plant, of up to 90 to 99% – a significant improvement for living conditions in nearby areas.
“In the open air, this would be equivalent to moving a kilometre away from the noise source, such as a large outdoor concert arena,” Hynninen says. He added that for city-dwellers, the change is equivalent to wearing earplugs or closing windows to alleviate traffic noise.
The project’s success depended on the SOPEVA team bringing its best ideas together.
“Previously it was common in the industry that organisations were more protective of their innovations,” Linde says. “Today, however, collaboration is the only way forward. Through combined effort and co-operation, we can bring together the best skills from all sectors and be as agile and robust as the market expects us to be.”
SOPEVA is a clear demonstration of Wärtsilä’s overall vision: enabling sustainable societies with smart technology, a goal that depends on open collaboration with partners such as VTT.