Environmental Initiatives



Our policy concerning nesting birds requires tree crews to look for nest building, chicks and eggs before they start any work. When the warm weather arrives, it means birds are chirping and trees are developing into canopies of green. After challenging Nova Scotian winters, we are able to perform work on our transmission and distribution lines to help prevent outages. That means you’ll likely see contractors along the province’s roads and highways trimming back trees, shrubs and ground cover to help maintain reliability of the system. Warm weather also means nesting season, so we’d like to tell you what steps we take to help protect and mitigate any potential effects on birds and their nests.

What We Do

  • We have more than 30,000 kilometres of power lines. With the amount of work that must get done each year to ensure reliable service, we cannot refrain from maintaining the system during nesting season. That said, we take our environmental responsibilities very seriously, including doing our best to protect our feathered friends.
  • Our policy concerning nesting birds related to our vegetation management program requires tree crews to look for nests, chicks and eggs before they start any work. If a crew sees any signs of such activity, they must stop work and ensure a minimum 10 metre buffer around the site.
  • If the contractor finds the nest of a larger bird, such as an osprey or eagle, the buffer zone is 100 metres. Contractors are required to provide records of these inspections. Every year, we have situations in which crews stop their work and relocate so as not to disturb nesting birds.
  • Our contractors leave all compatible vegetation, including shrub species that grow and eventually take over the site, lessening the amount of work contractors need to do over time. This also increases the amount of sustainable ecology that provides nesting opportunity.
  • We've also made significant efforts to complete required vegetation clearing associated with capital projects outside of nesting season. If clearing is required within nesting season, in most cases, a qualified birder is brought in to assess the area prior to any clearing taking place. If a nest is identified, an appropriate species dependent buffer is established around the nest and maintained until young have fledged.
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Every year we partner with Nova Scotia Museum of Natural History to give viewers the OspreyCam to track the family of Ethel and Oscar and their offspring



The former thermal generating plant on Halifax’s waterfront is now our main office known to our employees as “1H”, named after the original electrical substation that operated there. It became the first building in Atlantic Canada to achieve the Leadership in Energy and Environmental Design (LEED) Platinum certification from the Canada Green Building Council (CaGBC). The environmentally-friendly building also houses The Discovery Centre and Junior Achievement Nova Scotia


Building Waterfront
  • Construction for the new office building was completed in 2011.
  • Energy and water savings to the tune of approximately $650,000 a year
  • Harbour heat pumps use water from Halifax Harbour for heating and cooling purposes.
  • Chilled beams in the building decrease energy use and increase thermal comfort.
  • Over 75% of occupied spaces have access to daylight, with occupancy and daylight sensors used throughout the building to reduce or eliminate unnecessary lighting.
  • Rain water is collected and re-cycled for use in and around the building.
  • As the starting point of Halifax’s boardwalk, the building provides a new access point to the harbour.
  • The boardwalk level of the building houses a cafeteria open to the public.



  • Fossil fuels – mainly oil until the 1980s – supply most of Nova Scotia’s electricity
  • Generating facilities are built in proximity to domestic coal resources.
  • Our largest generating station, Lingan, was constructed in Cape Breton to burn coal.
  • Nova Scotia’s largest hydroelectric station, Wreck Cove, was constructed.
  • Point Tupper Generating Station, also based in Cape Breton, was converted from oil to burn coal.
  • Our Annapolis Tidal Power Plant, still the only facility of its kind in North America, was constructed.
  • We begin using low-sulphur coal and state-of-the-art low NOx burners at Unit 6 of our Trenton Generating Station. We added equipment called an electrostatic precipitator, designed to reduce emissions, to Unit 5 at Trenton.
  • Point Aconi Generating Station was constructed, opening in 1994. This plant remains our most environmentally-progressive coal burning facility with the fewest emissions.
  • Conversions at the Tufts Cove Generating Station were made to allow the plant to burn either natural gas or heavy fuel oil – whatever is more cost effective for customers.
  • An electrostatic precipitator is added to Tufts Cove Unit 2.
  • Coal mines in Cape Breton closed down, leading to the need to import most of our coal.
  • Two 50 MW combustion turbines are added to Tufts Cove to burn natural gas.
  • Electrostatic precipitators are added to Tufts Cove Units 1 and 3.
  • We enhanced our net metering program, raising the upper limit from 10 kilowatts to 100 kilowatts. Customers with a generation source of their own get full retail value for any excess power they produce. A growing number are taking advantage of this program.
  • Our first two wind turbines were installed at Grand Etang and Little Brook in 2002, while a larger push toward wind begins a few years later.
  • Digby Neck and Nuttby Mountain Wind Farms are fully operational, with a combined generating capacity of 80 MW.
  • 17.5% of Nova Scotia’s electricity is generated by renewable sources, meeting the requirement of 15%.
  • Tufts Cove Unit 6 is commissioned, a combined cycle combustion turbine that burns natural gas.
  • A 60 MW biomass power plant in Port Hawkesbury is commissioned, which supplies as much as 3% of the province’s electricity. It provides a source of firm renewable energy that can back up intermittent wind generation.
  • 20% of Nova Scotia’s electricity must be generated by renewable sources.
  • 26.6% of electricity was generated by renewable sources, surpassing the required target of 25%.
  • 29% of electricity was generated by renewable sources.

  • 40% of Nova Scotia’s electricity must be generated by renewable sources.
  • We're working towards 80% renewable and off coal by 2030.



Our commitment to clean energy has led us to partner with industry stakeholders to divert coal combustion products from landfills for re-use, providing significant environmental and economic benefits for Nova Scotians.



Coal Combustion Products (CCPs), including fly ash and bottom ash, are residual products collected after coal is burned in coal fired generating stations. We operate four such facilities in Nova Scotia, located in Trenton, Point Tupper, Lingan, and Point Aconi. Annually, we produce approximately 350,000 metric tonnes of CCPs that can be re-used for concrete production, cement manufacturing, waste stabilization, geotechnical fill, flowable fill, road building, asphalt, and many other applications. While a small percentage is re-used in the local concrete industry, the majority of this material is placed in dry storage at our ash management sites. In line with our clean energy strategy, diverting CCPs from landfills for beneficial re-use provides significant environmental and economic benefits for Nova Scotians.


Ash management sites associated with the four generating stations currently contain in excess of 10 million metric tonnes of CCPs, the majority of which are dry-stack stored with cap and cover. While total CCP production at Nova Scotia Power is expected to gradually decline with diminishing reliance on solid fuel, three million tonnes of CCPs are projected to be produced in the next 10 years.


We produce high quality CCPs that meet ASTM standards for many industries (ASTM C618, and ASTM C114 for Class F and Kiln Feed ash respectively). Our CCPs contain high quantities of silica, alumina, iron oxide, and calcium and only trace amounts of metals. The composition of CCPs depend on the fuel source and combustion process, and we have historically produced CCPs with high consistency due to our fuel blends and process stability.

Environmental Considerations

Using our ash residues presents a cost-effective and environmentally friendly solution to Ash Diversion customers. Recycling ash eliminates the energy cost and environmental footprint associated with producing novel additives and refining virgin materials by the cement industry. The removal of ash from our landfills will also help to remediate Ash Management Sites while reducing carbon emissions due to their reuse by other industries. As cement and concrete produced with our fly ash has greater durability than comparable products, the use of our ash will reduce future production requirements and the associated environmental impact.


Our fly ash can be used in concrete production, cement manufacturing, waste stabilization, geotechnical fill, flowable fill, road building, asphalt, and many other applications. Using our CCPs also reduces the amount of raw materials that need to be consumed, which once again decreases the overall environmental footprint.


Concrete containing fly ash is stronger and more durable than that produced with only cement. Our fly ash extends the life of infrastructure projects and incorporating our fly ash provides cost savings to concrete producers and lowers the overall cost of construction. We are progressing with an initiative to employ beneficiation technology to increase supply for the ready-mix concrete market.


Corrective ingredients are used in cement manufacturing to adjust chemistry and achieve ASTM specification. Our CCPs are high in on-spec and low in off-spec components, providing correction capability that is low cost, single source, and increases the quality of the cement.


Supplementing under-performing soils with fly ash has been shown to improved physical properties such as shear strength and load bearing capacity. Our fly ash provides a cost-effective means of stabilizing roadways, embankments, and construction sites.


Heavy metal and oil contaminated soils can be controlled with the introduction of our fly and CFB ash. Ash additions act to sequester toxic contaminants by forming dense soil aggregates, thereby preventing the spread of contamination and leaching to groundwater sources.


Our ash will require no further processing or refinement once delivered. Ash removed from landfills will be beneficiated prior to export and unlike comparable industry materials their quality will be very consistent and will be ready for use once passed to the customer


Exporting and Marine Terminals

Over time we plan to export fly ash by ocean going vessels at two locations. These are the Sydney International Coal Pier and the Point Tupper Marine Terminal in Cape Breton, Nova Scotia. Shipments of ash will likely be sourced from our four Generating Stations and will be transported to Sydney and Point Tupper to be loaded aboard ships for delivery to customers.

Both the Sydney International Coal Pier and the Point Tupper Marine Terminal are currently active coal import facilities for us.


Trenton Generating Station (TRE) opened in 1969. TRE-5 was commissioned in 1969 and underwent a multi-million dollar complete refurbishment in 2009, leading to improved efficiency of the unit. TRE-6 was commissioned in 1991. Total capacity of Trenton Generating Station is 307 MW.

TRE is located in the community of Trenton. TRE is situated adjacent to rail and located 65km North-East of Truro which is the rail transportation hub of Nova Scotia. 

More Information:

The Trenton Generating Station produces Class F and kiln feed fly ash from two thermal generating units at a rate of 108,000 metric tons per year, and bottom ash at a rate of 18,000 tons per year. Ash produced at Trenton has historically been dry stack stored at the Abercrombie and Trenton Ash Management Sites. The amount of stored ash totals approximately 4,000,000 tons.

Trenton Class F and kiln feed ash has applications in cement, concrete, and soil amendment industries.

Ash produced at Trenton will be loaded aboard proximally located rail facilities and shipped to points of export including Point Tupper. 

Ash Residue Composition: Trenton

ASTM Specs

POT-2 – Class F Ash

Class F Ash: ASTM C618

SiO2+Al2O3+Fe2O3 – 88.9%

SiO2+Al2O3+Fe2O3 >70%

SO3 – 0.73%

C <6%

CaO – 1.63%

H2O <3%

Alkalides (Na2O) – 0.89%

45um Fineness >65%

Moisture – 0.05%

Fineness (% retained on 45 μm sieve) – 16.9%

Specific Gravity (g/cm3) – 2.39

TRE-5 – Kiln Feed Ash

Kiln-Feed Ash: ASTM C114

SiO2+Al2O3+Fe2O3 – 87.49%

SiO2+Al2O3+Fe2O3 >70%

SO3 – 1.12%

C <20%

CaO – 3.21%

H2O 9-15%

Alkalides (Na2O) – Trace

25 mm Fineness 100%

Moisture – 0.001%

Fineness (% retained on 45 μm sieve) – 12.9%

Specific Gravity (g/cm3) – 2.49


Point Tupper

Point Tupper Generating Station (POT) was commissioned as an oil-burning unit in 1973. It was converted to coal and recommissioned in 1987. Total capacity of Point Tupper Generating Station is 150 MW.

POT is located in the community of Point Tupper in the Richmond County area.  POT is situated adjacent to our Point Tupper Marine Terminal (PTMT) in the Canso Strait.

More Information:

A single Generating Unit at Point Tupper produces fresh Class F and Kiln Feed fly ash at a rate of 34,000 tons, and bottom ash at a rate of 4,000 tons annually. Historically produced ash has been dry stored at the nearby Bear Head Ash Management Site in the estimated total amount of 1,250,000 metric tons.

Two ash varieties are produced at Point Tupper. These include Class F, Kiln Feed. These ash types can be applied to cement and concrete production as well as soil stabilization and solidification industries.

Initially ash stored and produced at Point Tupper will be relocated to the nearby Port Hawkesbury Paper Marine Terminal prior to ship-loading and export to customers.

Ash Residue Composition: Point Tupper ASTM Specs

POT-2 – Class F Ash

Class F Ash: ASTM C618
  • SiO2+Al2O3+Fe2O3 – 81.77%
  • SiO2+Al2O3+Fe2O3 >70%
  • SO3 – 1.06% 
  • C <6%
  • CaO – 3.02%
  • H2O <3%
  • Alkalides (Na2O) – 0.94% 
  • 45um Fineness >65%
  • Moisture – <0.1%
  • Fineness (% retained on 45 μm sieve) – 19.1%
  • Specific Gravity (g/cm3) – 2.462


Constructed in the 1970s, Lingan's four units were commissioned separately from 1979-1983. Lingan is Nova Scotia Power’s largest generating station. Total capacity of Lingan Generating Station is 620 MW.

LIN is located in community of Lingan, which is an old integral part of the Cape Breton Regional Municipality’s historical coal mining community.  Lingan is proximal to marine via 15km rail loop to Nova Scotia Power’s International Coal Pier (ICP) in Sydney Harbour.

In 2012 Nova Scotia Power announced that two of Lingan's units would be operated only on a seasonal basis due to decreased industrial load, increased renewable energy use and to meet environmental requirements.

More Information:

The Lingan Generating Station produces Class F and Kiln Feed fly ash from four units at a rate of over 100,000 metric tons per year, and bottom ash at a rate of 16,000 metric tons per year. Ash produced at Lingan is dry stacked stored in landfill near the plant site in the amount of 5,500,000 metric tons.

As the ash diversion program expands the ash will be stored at Nova Scotia Power’s International Coal Pier (ICP) in Sydney Harbour , this is planned to be the primary point of export for Lingan CCP products. Ships will be loaded here with Lingan ash before delivery to our  customers.

Ash Residue Composition: LinganASTM Specs

Class F Ash

Class F Ash: ASTM C618

  • SiO2+Al2O3+Fe2O3 – 79.51%
  • SiO2+Al2O3+Fe2O3 >70%
  • SO3 – 1.06%
  • C <6%
  • CaO – 3.02%
  • H2O <3%
  • Alkalides (Na2O) – 0.91%
  • 45um Fineness >65%
  • Moisture – <0.1%
  • Fineness (% retained on 45 μm sieve) – 20.3%
  • Specific Gravity (g/cm3) – 2.467

Point Aconi

Point Aconi (POA) opened in August 1994.  The plant’s circulating fluidized bed technology means it can use petcoke in its boiler while significantly reducing emissions. Due to its design, Point Aconi is primarily fueled by petcoke, which is a solid by-product of the oil refining process.  Total capacity of Point Aconi Generating Station is 171 MW.

POA is Located in the rural community of Point Aconi.

More Information:

The Point Aconi Generating Facility is unique among our facilities in that it uses Circulating Fluidized Bed technology. This process requires the addition of limestone and results in ash residue with higher than typical calcium content. CCB ash residue holds particular value in soil amendment applications.

CCB fly ash and bottom ash residues are produced at Point Aconi at an annual rate of 90,000 and 80,000 metric tons respectively. Historically produced residue is stored at Point Aconi in dry-stack storage in the amount of 3,000,000 tons.

Ash Residue Composition: Point AconiASTM Specs

Class C Ash

Class C Ash: ASTM C618

  • SiO2+Al2O3+Fe2O3 – 12.92%
  • SiO2+Al2O3+Fe2O3 >50%
  • SO3 – 26.5%
  • C >50%
  • CaO – 50.23%
  • H2O <3%
  • Alkalides (Na2O) – 0.34%
  • 45 mm Fineness <34%
  • Moisture – <0.1%
  • Fineness (% retained on 45 μm sieve) – 41.4%
  • Specific Gravity (g/cm3) – 2.812


We operate a 60 megawatt biomass power plant in Port Hawkesbury, which supplies as much as 3% of the province’s electricity. Biomass is a renewable energy source used around the world. The facility helps us reach renewable energy requirements and provides a source of firm renewable energy that can back up intermittent wind generation.


We offer a variety of fly and Kiln-Feed ash residues to our customers. As the ash produced at our four Generation Stations is distinct, we can provide tailored ash products for use in range of industries.

We offer a variety of fly and kiln-feed ash residues to our customers. As the ash produced at our four generation stations is distinct, we can provide tailored ash products for use in range of industries.

Though ash composition is variable and depends on plant operating conditions, fuel blend, and chemical treatment, commonalities exist for the ash produced across our Generation Stations. Our fly ash contains:

  • Silicon Dioxide (SiO2)

  • Calcium Oxide (CaO)

  • Iron (III) Oxide (FeO2)

  • Aluminum Oxide (Al2O3)

Dependent on the fuel blend used, our fly ash may also contain trace amounts of other materials.

As fuel blends and operating conditions have been carefully monitored for consistency over the operational life of each plant, the ash residue produced has also remained consistent in terms of composition. As a result, we have a large inventory of ash produced at each plant, which deviates very little with respect to chemistry and physical properties.

The following table compares ash residue compositions by generation station to the corresponding ASTM specifications for Class F, Class C, and Kiln-Feed Ash residues.

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Canada’s Ocean Supercluster announced the Ocean Aware project in July 2020. The Ocean Aware project will develop and commercialize world-class solutions for monitoring fish health, fish movement and the environment and supporting both profitable and sustainable practices in the ocean.


The Ocean Supercluster will provide $13.74 million in funding for the project, with $15.7M in funding coming from industry partners. Ocean Aware is led by Innovasea. Partners include: Emera, NS Power, Ocean Choice International, Irving Shipbuilding, Dartmouth Ocean Technologies and Xeos Technologies, with the support of the Ocean Tracking Network, Dalhousie University, Fisheries Marine Institute of Memorial University, the Department of Fisheries and Oceans, and others.

Our Role

We will be providing access to our White Rock Hydro System and providing our expertise as Innovasea collects important data on different species.

This technology will give us a better picture of the presence and movement of fish in real time and allow us to build on some of the work we have done, to protect fish habitat.

This is about investing in our future and continuing to look at ways to ensure we are providing reliable, affordable power to our customers while operating in the most efficient, environmentally friendly way.


frequently asked questions

Why are you choosing to test this at the White Rock Hydro station?

White Rock is a good location because it has a number of moving parts with the canal, head pond and downstream passage area.  We have made a number of improvements at our White Rock facility including necessary upgrades to our fish passage structures that allow fish to move around barriers such as dams.  This technology will enhance that work.  There are multiple species at White Rock and we have seen fish activity increase significantly in each of the last four years (over a million in each of the last four years – up from about 400,000).

For the latest information, visit: https://oceansupercluster.ca/ocean-aware-project-announcement-news/

Why is this important?

Protecting our environment is a priority for us and is an integral part of our decision making.  It is important to have good information around fish at our facilities in order to operate efficiently and in the most environmentally friendly way.  We want to continue to have the best information we can to ensure our due diligence when it comes to protecting fish habitat and the environment.  The opportunity to work with like-minded partners to develop and test this leading-edge technology will assist us in better tracking and understanding the fish health and movement in our operating facilities.

How does this technology work?

This technology will help better detect the presence and movement of fish in the water around our facilities in real time.  It takes an electronic picture to get a better idea of what’s going on.  It will also develop and test better sensors in addition to the algorithms/software.  Having this information allows us to continue to look at ways to avoid impact to fish and operate in an environmentally friendly way.




Many of our hydro facilities have been in operation for 100 years. We have a long history and ability of operating safely while respecting the environment. We continue to meet the Canadian Dam Association Safety Guidelines and operate within the requirements of our regulator. Nothing is more important than the safety of our employees and customers. As we continue to grow our use of clean energy, we are committed to maintaining our hydro facilities and the surrounding environment. Our operation of these facilities includes public and employee safety, protection of the environment and the generation of electricity.


Each hydro system is operated in accordance with a Water Approval for Storage/Withdrawal of Water under the Nova Scotia Environment Act. These approvals are renewed on a ten-year basis and we are currently in the 3rd round of relicensing.

It is important that regulators, community members and organizations, Mi’kmaw communities and organizations, the general public and any other user of the watershed are able to participate in the relicensing process and have a means to provide valuable information toward the ongoing operation of the system.

During conversations with these interested parties, the most common issues raised and addressed include fish passage, ecological maintenance flow, reservoir elevation, flowage rights, recreational access, dam safety, commercial fishing, fish species recovery and habitat impacts.

We gather and provide information to Nova Scotia Environment as part of the application to relicense a system. A report is written to give a complete picture of the previous 10 years of operation. An overview of the system includes a summary of any changes, dam safety information, and a description of compliance with regulatory requirements. Water quality studies provide an overview of a stream and reservoir sampling program. Fish and fish habitat and species of concern are also investigated. Mi’kmaq cultural heritage is recognized as an important part of the systems. Once all information is complied and reviewed, recommendations for compliance are described.



We are working to relicense several systems at this time including the Sissiboo Hydro System and Roseway Hydro System. Applications for these systems are due to be submitted June 30, 2022. Feedback is important to us so we can make informed decisions for our customers. If you have questions or want to better understand these systems, we encourage you to submit them by March 31, 2022 to allow us time to review and consider them as part of our application process. The deadline for public comment is March 31, 2022.

You can reach us with any questions or comments at hydrorelicensing@nspower.ca

Sissiboo watershedThe Sissiboo Hydro System is located in Digby County, in the southwestern part of the Nova Scotia. Sissiboo Hydro drains into the Sisiboo River, which passes through the village of Weymouth and empties into St. Marys Bay.

The Sissiboo Hydro system has a drainage area of 621.6 km2 and consists of three generating stations along a thirty-two kilometer stretch of the Sissiboo River. The main reservoir is Fourth Lake, which collects all run-in from the upper part of the system. Water flows through the Fourth Lake generating station and into Sissiboo Grand Lake Reservoir, where the outflowing Sissiboo River joins the Wallace Branch of the Sissiboo River. The combined flow enters the Sissiboo Falls flowage and generating station, and on to the Weymouth Falls flowage and generating station, where it makes its way out of the river mouth and into St. Marys Bay. The Sissiboo Hydro System was constructed from 1958 to 1962; there was a significant redevelopment in 1983 when the Fourth Lake generating station was installed.

Roseway watershed

The Roseway Hydro System is located on the Roseway River in Shelburne County, Nova Scotia. The system originates in a chain of small lakes located at the junction of Digby, Yarmouth, and Shelburne counties, and drains an area of approximately 524.4 km². It flows in a North to South direction and empties into Shelburne Harbour.

The hydropower system was constructed in the 1930’s and had been in operation continuously up until 2012. At that time, the system was partially decommissioned. Currently, there is no active water management or electricity generation on this system. The dam and spillway structure are still in place however, the gates have been removed leaving the system as run of river.

Air Emissions Reporting

View the past several years of air emissions from our power plants.



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