- Ottawa, Ontario
A recently completed pilot project by the National Research Council of Canada (NRC) and NB Power has shed new light on saving energy by keeping voltage low but still within the allowable limits.
This year-long pilot began in 2019, and was led by the High-performance Buildings program within the NRC’s Construction Research Centre. NB Power partnered with the NRC, Siemens Canada, and Natural Resources Canada on this project to study the conservation of energy in New Brunswick by means of voltage reduction. The project pushed the envelope on conservation voltage reduction (CVR), a well-established method for conserving energy by managing voltage. Results of the study confirmed how electric utilities and their customers can benefit from CVR through the use of smart technology.
Since voltage drops as energy transfers along the lines from a substation to its destination, in the absence of smart technologies to optimally adjust the voltage, utilities keep voltage at a level higher than the minimum specified by technical standards. While not optimal for energy savings, this approach ensures that the electricity delivered to customers remains within the limits prescribed by the relevant standard (published by the CSA Group, formerly the Canadian Standards Association). CVR is a smart technology that dynamically adjusts and optimizes the voltage at the substation and along the distribution line, so that the voltage at all customers connected to the substation is within the permissible range and as low as possible to be useable and to save energy.
New Brunswick was an ideal testing ground for new CVR frontiers, since its electricity usage and weather are unique. Electricity demand is highest in the winter because homes and businesses use it for space heating, and the province has frequently fluctuating weather affecting energy usage. “Because we have a high concentration of electric heating, we wanted to do the project for a 12-month period,” says Ken Goggin, Energy Smart Project Manager, NB Power. “Our power usage peaks in winter, so we needed to context that in all seasons.”
By using CVR, utilities can improve efficiencies, save energy and reduce demand. Given New Brunswick’s unique challenges influencing energy usage, this needed to be quantified before the custom solution could be rolled out across the province. The NRC began by devising measurements and data analytics to gauge savings from residential, commercial and industrial buildings when an electrical distribution system operates at the lowest voltage allowed by the relevant CSA standard.
“We also did an exhaustive international literature search of state-of-the-art CVR methods used by electric utilities,” says the NRC’s Team Leader, senior researcher Ajit Pardasani. “Combined with interviews of project teams in Canadian electric utilities, this helped us develop best practice guidelines for NB Power.” The NRC teams from the Construction and Metrology Research Centres then gathered and analyzed data from the pilot to estimate energy savings.
The 4 pilot substations selected for the CVR study are in Bathurst, Fredericton, Moncton and Quispamsis and represent a good cross-section of NB Power’s entire grid. “For CVR, we upgraded these substations and installed 700 smart meters that monitor about 5,000 customers’ voltage patterns and feed the data back to the CVR control system,” adds Goggin. A sample set of the smart meters provide data every 15 minutes so that NB Power can adjust the voltage up or down without letting it drop below the minimum limit.
Taking the pulse of CVR
Tests showed that energy consumed by buildings and homes over the winter heating period was reduced by 2.3% to 2.7% on days when CVR was used. Spring saw similar savings despite the fact that the COVID-19 pandemic shifted energy usage patterns. Tests conducted over the year showed that the average substation voltage can be safely reduced by 3.4% to 5.6%.
But savings are not just financial. CVR can cut greenhouse gas emissions by up to 16,500 tonnes in the province. Smart technology can meet growing customer expectations for affordable rates, clean energy and fingertip services to manage their own usage. And CVR helps utilities maintain their competitive edge as new players enter the electricity market.
Flowing into the future
“The lessons learned from this research have helped us develop a roadmap to expand CVR across the province,” says NB Power’s Goggin. Kinectrics Inc., experts in electrical testing and engineering, analyzed the potential benefits of CVR for NB Power before the start of the pilot. Analysis of pilot study data by the NRC showed 3.4% energy savings over the 1-year period with a 5% average reduction in voltage enabled by a CVR system using smart meters. This will also help the utility build a smarter, cleaner, more reliable and efficient power grid for New Brunswickers.
Goggin points out that NB Power has commissioned the NRC to leverage data from the pilot to conduct savings projections on a larger scale over the next year. “Project teams from the NRC and NB Power have worked together for many years,” he adds. “The NRC is a trusted partner – an unbiased, reputable third party with vast research capacity and experience that lends credibility to all our research.”
Smart grid technologies and real-time systems are the future. What the NRC and NB Power learned from this study can apply other electric utilities, benefitting the companies, their customers and shareholders. And that’s a powerful win-win.