Solar Electric Generation Northwest Territories, Canada in 2024Â
This article re-visits hybrid diesel-solar photovoltaic (PV) electric generating facilities at two small communities of fewer than 200 inhabitants in remote parts of Northwest Territories of Canada following a 2021 report (Boleneus, 2021). It highlights the limited yet important value of solar installations to tiny populations, demonstrates very high cost of incorporating battery storage, and emphasizes the low level of efficiency of hybrid systems due to extended wintertime darkness with the unavoidable requirement for diesel-electric generation.
The facilities are located at Fort Simpson (latitude 61.7oN.) and Colville Lake (latitude 67oN.), an area served by Northwest Territories Power Corporation. NTPC serves thirty-five communities in NWT and twenty-one of the communities use renewable systems to supplement diesel generation of electricity. Fort Simpson’s solar facility has remained unchanged since 2014, but Colville Lake enlarged its solar generation and added battery storage to reduce use of diesel. Solar provides only 1% of NTPC’s electricity generation along with diesel generating 56%, hydro 35%, and natural gas purchases at 5%. Solar installations allowed NTPC to reduce diesel use, greenhouse emissions and number of power outages. This article examines the electricity generating records at communities and examines cost and other aspects of solar PV- and diesel-electric generation.
Colville Lake is located about 240 air miles (395 km) south of Tuktoyaktuk, NWT on the north coast bordering the Beaufort Sea while Fort Simpson is located 380 air miles (615 km) south from Colville Lake and 128 air miles (307 km) north of the NWT boundary with British Columbia. (Map from Government of Northwest Territories).
Power Outages
Each site uses solar to generate electricity during extended daylight hours. Solar PV generation also conserves diesel fuel, helps reduce troublesome power outages that according to CBC News (Limberlink, 2021) are more common when relying solely on diesel generation. Diesel supply is concerning because diesel transport is possible only on winter-only roads during January-February each year. Northwest Territories Power Corporation says its average customer experienced 7.6 outages per year lasting an average of 78 minutes in 2024, a decrease from 12 outages per year in 2014 each lasting 23 minutes (NTPC annual reports, 2014, 2024). Because this outage record is averaged across the service area it does not represent individual communities. Colville Lake residents say the number of times that power went out was unacceptable so that moving to renewable sources should continue (CBC News, 2021) as outages at Colville Lake have been reduced from 51 in 2014 to 10 by 2021 or five years after launching the hybrid system.
Solar PV
The Fort Simpson solar PV-diesel hybrid project consists of 436 solar panels with an installed capacity of 104 kW at a cost of $1.07 million (NTPC). At Colville Lake, the solar PV-battery storage-diesel hybrid consists of 350 kW diesel (3 units) and 136.5 kW solar PV linked to 200 kW/232 kWh battery storage at a cost of approximately $7.5 million-$8 million (Google Earth image at Colville Lake). The Colville Lake project anticipated an annual fuel savings of 80,000 liters of diesel by solar PV generating 112,000 kWh of electricity.
Source: Google Earth at Colville Lake
The chart below illustrates temperature and solar PV electricity-generation of both projects for the most recent one year ending February 28, 2025. The temperature and solar PV curves are smoothed using 14 period averaging (14-per. Mov. Avg.). The most notable observation is the long period of darkness at Colville Lake (red curve) interrupted by lengthening daylight period beginning in early March compared to a lengthened period of darkness at Fort Simpson (blue curve). Both sites quickly respond to daylight beginning in February at Fort Simpson and March after 80 days in darkness at Colville Lake.
Source: Compiled from NTPC’ operator data1 2
The following table summarizes site data to compare the earlier periods (either 2019-2020 or 2020-2022) to the recent 1-year period for both Fort Simpson and Colville Lake. The period of time that facilities generated no electricity is 1 day and 80 days at respective sites. Each generated more electricity from solar power during the year 2024-2025 than the earlier time periods with electricity generation rising at Fort Simpson from 231 kWh/day to 301 kWh/day and 137 kWh/day to 210 kWh/day at Colville Lake.
Cost of Diesel and Solar Installations
The following chart compares the calculated cost over a period of 15 years of installing and operating both diesel and solar generating facilities in Northwest Territories at Fort Simpson and Colville Lake. The cost of installed sola PV hybrid system is based on the Fort Simpson 437-panel 104-kilowatt installation that began generating in 2012-2013 at a cost of $1.07 million with this cost updated to 2024 (Infomine, 2025). The updated cost is then applied proportionally to the 31.7% larger Colville Lake solar facility. The annual operating cost of solar PV is assumed at 2% of the installed cost.
The estimated cost of the diesel generator includes installing two 100 kW Generac SD100 gensets with addition of 100% of purchase for installation. Operating cost of gensets is estimated by use of Mining Cost Service (Infomine, 2025) based on annual solar PV hours of generation. The period of operation for the diesel gensets is not operating hours for the entire year but a lesser amount to equate hours to replace solar PV generation to accommodate this comparison, or 1,007 hours and 700 hours for Ft Simpson and Colville Lake, respectively. A 25% premium for transport is added to diesel cost (14,707 gallons [55,665 L] at Ft Simpson and 10,216 gallons [38,667 L] at Colville Lake) and 50% premium is added to other genset operating costs for parts and labor (Mining Cost Service, Infomine, 2025).
The chart shows solar PV and diesel costs for Fort Simpson (red symbols) and Colville Lake (blue symbols). The comparison clearly shows that installation of solar PV at $1,476,600 at Fort Simpson and $1,944,682 at Colville Lake is a far larger cost than diesel gensets at $360,000. The annual operating cost for diesel gensets for the comparison is $29,500 at Fort Simpson and $38,900 at Colville Lake.
Source: Costmine Intelligence analysis
From this analysis summarized from the chart above, the additional premium paid (table below) for solar over cost of diesel generation to provide the same electricity in year 1 at Fort Simpson is 310% ($1.1 million) and 440% ($1.5 million) at Colville Lake with this cost falling through year 15. Loss in efficiency or replacement due to age is ignored. One can conclude that to install and operate a solar plant is more expensive than diesel to generate the same electricity.Â
Discussion
The useful life of generator sets and solar panels is highly variable. Assuming regular maintenance the lifetime of a genset is long but unknown. For solar panels, the National Renewable Energy Laboratory (Deline and others, 2024) finds that panels degrade by 0.8% per year, so efficiency of a 15-year-old panel will degrade by 11.3%, or degrade by a total of 21,168 kWh in 15 years. Grist.org finds that solar panels are expensive to recycle at a cost of $50 per panel including transportation and that recoverable aluminum, silver, copper, and glass contributes only $3 in value. An EPRI (2018) estimate found the cost of decommissioning is 6.7% of installation and salvage value of aluminum and copper contributes 1.95% of the installed cost. Energy Matters (www.euanmearns.com) reports the mean scrappage age in Germany is 17 years. Battery electric storage systems degrade variably by 15% to 20% over ten years depending on cycling strategies employed (Muhlbauer 2025). Efficiencies of solar PV suffer from several deficiencies as listed below.Â
Source: www.photovoltaics-software.com.
The Colville Lake hybrid system is unusual as it includes a 200kW/232 kWh lithium-ion battery, not found at Fort Simpson. For this analysis the battery storage is ignored to remain consistent in the comparison. The solar/battery storage is able to provide about 50% of the community’s electrical needs for the April through August period with the combined solar PV-plus-battery providing 17% of power needs year-round. The battery storage is very costly, adding at least $6.1 million for battery-plus-inverter to the $1.4 million solar PV, so the battery backup segment is 4.3 times or more costly than the solar PV segment at Colville Lake. CBC News (Limberlink, 2021) gives the per-kW-hour battery storage costing $1,344 per kWh and $8 million for the entire system and consistent with battery costs in contiguous U.S. in 2022 ranging from $1,500 to $3,000 per kW (power capacity) and $500 to $2,000 per kWh (energy capacity) (US Energy Information Administration, 2025).
Conclusion
Hybrid renewable energy systems consisting of solar photovoltaic-diesel generators or solar-generators-battery storage are useful at remote communities in NWT to reduce the number of power outages experienced. A second advantage in use of either type of hybrid system is savings of diesel cost as supplying diesel to remote communities is challenging. The size of the solar PV in kilowatts is small and affordable with systems ranging from 104 kW to 137 kW. Surprisingly however, the solar PV systems rapidly respond to an increase in daylight hours early each year that follow long periods of darkness to as much as 80 days at Colville Lake.
Hybrid renewable is much more expensive to install, by 310% for solar PV to 440% more for solar PV plus battery storage compared to diesel generator or gensets. Another disadvantage of solar PV systems is the inability to operate in darkness during all seasons with this limitation requiring diesel gensets to be available as a full-time backup source of electric generation. The efficiency of solar PV systems used in northern communities when compared to their installed capacity is low, ranging from 6% to 12% although solar PV responds to the first appearance of daylight early each year.
If regular maintenance is assumed, diesel gensets may yield a longer life than the solar PV systems with a lifetime of 15 or more years before replacing.
References
Boleneus, D., 2021, Using the sun to power Canada’s remote mines. September 10, 2021 Canadian Mining Journal. https://www.canadianminingjournal.com/featured-article/using-the-sun-to-power-canadas-remote-mines/
Deline, C., Jordan, D, Sekulic, B., Parker, J., McDonald, B., and Anderberg, A., PV lifetime project, 2024 annual report. National Renewable Energy Laboratory https://research-hub.nrel.gov/en/publications/pv-lifetime-project-2024-nrel-annual-report
Electric Power Research Institute (EPRI), 2018, PV plant decommissioning salvage value, conceptual estimate, 2018 Technical Report, https://restservice.epri.com/publicdownload/000000003002013116/0/Product
Energy Hub, 2021, Cost of solar power in Canada, 2021 https://www.energyhub.org/solar-energy-maps-canada/
Energy Matters, Energy return of solar PV. The Energy Return of Solar PV | Energy Matters  https://euanmearns.com/the-energy-return-of-solar-pv/
Infomine, 2025, Mining Cost Service-Chapter CI (Cost Indexes); Chapter EP (Electric Power), 2024 https://www.costmine.com/mining-cost-service/
Limberlink, L. 2012. Northern climate poses challenge for Colville Lakes hybrid power system CBC News
Northwest Territories Power Corp. a, NTPC https://www.ntpc.com/smart-energy/how-to-save-energy/fort-simpson-solar-energy-project Data sources: Fort Simpson //enlighten.enphaseenergy.com/pv/public_systems/wBzY58297/overview Colville Lake //enlighten.enphaseenergy.com/pv/public_systems/9qYr847770/overview
—- b, Annual reports, 2014, 2017-18, 2024. https://www.ntpc.com/sites/default/files/2021-02/ntpc–annual-report–2015.pdf
—- c, Fort Simpson Solar Project https://www.ntpc.com/energy-alternatives/current-alternative-energy-projects/fort-simpson-solar-energy-project
Photovoltaicsoftware.com, https://photovoltaic-software.com/DG/files/PV-power-calculation-basic.xls
Muhlbauer, M., 2025, Using battery aging data to prepare BESS for wholesale markets. Powermag.com. p. 14-15
Provost, M., Turcotte, D, Ninad, N., Poissant, Y., Prieur, A. and CanMet Energy 2019, Performance analysis of the PV-storage-diesel hybrid microgrid of Colville Lake Northwest Territories, Canada based on one year of monitored data. Natural Resources Canada, powerpoint //microgrid-symposiums.org/wp-content/uploads/2019/08/03_DaveTURCOTTE.pdf
Solar energy maps Canada. Energy Hub. https://www.energyhub.org/solar-energy-maps-canada/
US Energy Information Administration, 2025, Figures 10 and 11 in: U.S. battery storage in the United States: An update on market trends in 2024 https://www.eia.gov/analysis/studies/electricity/batterystorage/
Notes:
[1] Colville Lake Hybrid Solar/Battery/Diesel Generation
https://enlighten.enphaseenergy.com/pv/public_systems/xrDs481206/overview
https://enlighten.enphaseenergy.com/pv/public_systems/9qYr847770/overview
[1] Fort Simpson Solar PV https://enlighten.enphaseenergy.com/web/wBzY58297?public=1
