As a crown corporation owned by the provincial government of British Columbia, BC Hydro is required to procure equipment and services through a competitive bidding process. The utility enlisted the help of Quanta Technology to develop requests for proposals for both the battery and systems integrator. Developing the selection criteria for the battery technology required meeting the reliability requirements of the organization. As a result, only the sodium-sulfur (NaS) battery technology, supplied by NGK Insulators, could demonstrate a proven track record with the battery size and function that BC Hydro required.
The utility chose S&C Electric as the systems integrator because it has successfully installed more than 12 MW of sodium-sulfur BESS. In posting separate requests for proposals for the batteries and system integrator, BC Hydro hoped to make the project open to a larger number of proponents; however, in retrospect, a single vendor proposal and contract would have been simpler to manage.
The biggest hurdles to completing the battery and system integrator contracts proved to be the standards definitions, generally boilerplate to the utility, with which the new technologies did not necessarily comply. For example, BC Hydro did not have a standard for a storage management system (SMS), so the utility included the Canadian Standards Association standard for small low-voltage inverters it had adopted. At the time, the inverter in S&C Electric’s PureWave SMS had not been certified to that standard so a waiver was required, although certification has since been achieved in a recent application in Canada.
Not having a full understanding of the requirements put the procurement team in the unusual position of looking to the proponent for guidance on the contract language while still protecting the utility’s interests. Completing negotiations for both contracts required all parties to proceed to the first level of design with a degree of cooperation and openness not typically seen during a standard procurement process.
The location, environment and climatic conditions in British Columbia’s East Kootenay region presented the team with a unique design challenge. Initial plans called for the NaS batteries to be installed in external weatherproof enclosures suitable for ambient temperatures as low as -40°C (-40°F). However, through a more detailed study of the climate in the proposed locations, potential temperatures of -50°C (-58°C) were considered possible. A revised plan for two climate-controlled buildings with the batteries in racks proved to be prohibitively expensive and almost ended the project before it had even started.
A third option, proposed by the systems integrator, S&C Electric, was to use the external battery enclosures installed inside prefabricated buildings. This solution would provide protection from snow and sufficient insulation for the internal temperatures to never to drop below -40°C. In addition, NGK modified the design of the battery module enclosures so all electronic components would be confined to one end of the installation where the ambient temperature could be further controlled. This revised design required input and cooperation from all stakeholders. Support from Parks Canada and Natural Resources Canada was invaluable to being able to fast-track an agreement to the process.
For automated function and monitoring of the battery systems, telecommunications was required at both the Golden and Field sites back to BC Hydro operations, between the sites and the Golden substation, and between the Field site and the point of islanding.
In 2011, the communication options for the Field battery located in Yoho National Park were limited by available providers, terrain, climate and vegetation. Landline services were limited, there was no cellular infrastructure and the satellite links were not guaranteed because of steep valleys and heavy precipitation. Local wireless communication was difficult given the distances and pathway of the distribution lines through densely forested parkland. The challenge was to find an economic solution with acceptable reliability.
After much deliberation, the long-haul communication from the Field battery site to the Golden substation and back to BC Hydro operations would be provided by C-band satellite, and the short-haul communications, between the islanding disconnect point and the battery site, would be provided by a 900-MHz SpeedNet radio. The design of the radio portion required a fiber section from the site through dense forest to the open road and then multiple radio hops on two new poles to find a reliable signal path. Since the time of the original design, cellular communication has been established in Field and this option is now used by S&C and NGK to monitor their systems remotely.