Sustainability glossary, Acronyms and units

The page explains some of the terms, units and acronyms used in Fortum’s Sustainability website.


The decreased ability of a habitat, such as a lake or forest ground, to neutralize the acid fallout from the air; as a result, the pH level drops, i.e. water becomes more acidic. Flue-gas emissions, like sulphur dioxide and nitrogen oxides, contribute to acidification.

Best available technology (BAT)
The most advanced commercially available processes, equipment and techniques that can be practically adopted to limit emissions and waste. BAT is a central principle in plant permit processes.
The existence of a wide variety of plant and animal species in their natural environment (diversity in habitats and species and genetic diversity within species).
A product generated in conjunction with power and heat production or in the cleaning of flue gases that can be utilised. Examples include ash and gypsum.
Carbon dioxide
A gas generated from the combustion of fossil fuels containing carbon, see Greenhouse effect.
Carbon dioxide-free production
In Fortum's reporting the term carbon dioxide-free production refers to hydro, nuclear, wind, solar and wave power, which do not generate emissions in the production phase, and the use of biomass energy and the thermal energy generated by heat pumps from ground, water system or waste heat.
Verification of compliance of operations with an environmental, safety or quality management system standard (e.g. ISO 14001). Verification is made by an accredited organisation.
Circular economy
In a circular economy, added value in products is retained as long as possible and waste production is eliminated. For us, the circular economy means that materials are recycled as much as possible and hazardous substances are removed from circulation.
Climate change
A long-term change in the global or local climate, e.g. in precipitation, temperatures and wind patterns. Climate change can be caused by events related to e.g. oceanic thermal mechanisms, solar activity, volcanic activity, and human activity. Commonly, the term climate change refers to the global warming caused by the increased greenhouse gases resulting from human activity.
Code of Conduct
The Code of Conduct defines the foundation of Fortum’s way of operating everywhere. The Board has approved the Code of Conduct and it is based on Fortum’s shared values.
Combined heat and power production (CHP)
The simultaneous generation of heat and electricity at a power plant in which the thermal energy of the turbine steam used for power production is utilized by industry or as district heat. Combined heat and power production achieves a high co-efficiency rate (as much as 90%), i.e. the fuels needed in production are used more efficiently.
Condensing power
Electricity production in a power plant where thermal energy is not utilized, but is cooled using cooling water.
Contaminated soil
Per the Finnish Environmental Protection Act (527/2014), a land area is considered contaminated if waste or other substances have been abandoned, discharged or deposited in soil in a manner resulting in such degradation of soil quality as may cause hazard or harm to health or environment, significant decline in amenities or other infringement of public or private interest.
Cooling water
Water used to condense the steam that is used in electricity production at a power plant. Cooling water is taken from a water system (sea, lake) and is returned to it about 10 oC warmer.
Eco-labelled energy
Electricity produced in accordance with certain criteria in an environmentally sound manner and with renewable energy sources. For instance, ”Ekoenergia” in Finland and ”Bra miljöval” in Sweden.
Electricity capacity market
In Russian electricity markets all players in the market participate in so-called capacity markets in which the producer is guaranteed a certain price level independent of electricity price fluctuations. Capacity markets aim to encourage new investments in electricity production.
Electricity derivatives market
With electricity derivatives a producer or seller can agree on the electricity price e.g. for one year ahead. Also electricity derivative prices are determined on the basis of supply and demand. In addition to electricity producers, brokers and consumers, players in the derivatives markets include investors, such as international banks.
Electricity retail market
In the electricity retail market consumers can choose their electricity seller within their own country. Electricity retailers make electricity agreements with consumers. The selling price of electricity is based on the wholesale price and the seller’s margin. Consumer prices follow with a delay the fluctuation of the wholesale price determined in the exchange.
Electricity spot market
A market in which trading is done with next day’s electricity product. Players in spot markets daily send their price offer in which they disclose the price and volume of the electricity they are willing to buy or sell at each hour of the following day.
Electricity wholesale market
In the wholesale market electricity producers, retailers and big electricity users buy and sell electricity in the exchange. The Nordic power exchange Nord Pool is an important part of the electricity wholesale market. Nord Pool’s common market area includes Denmark, Norway, Sweden and Finland. Both spot trading and derivatives trading is conducted in the wholesale market.
Emissions trading
A scheme in which emissions have economic value and in which emissions allowances or credits are bought and sold. At the moment the most significant emissions trading scheme is the EU’s carbon dioxide emissions trading scheme.
Feed-in tariff
A system that guarantees electricity producers an additional or fixed price for electricity produced most often with renewable energy sources. With the feed-in tariff system, a government can shape the electricity production structure; the system typically encourages the use of renewable or domestic energy sources.
Fly ash
A by-product generated in connection with solid-fuel combustion. Fly ash can be utilised as made-up ground and in mine filling.
Greenhouse gas
A gas that absorbs heat radiation and traps it in the atmosphere, thus strengthening the greenhouse effect. The main greenhouse gases are carbon dioxide and methane.
Guarantee of origin
In line with the EU directive, an electricity guarantee of origin contains information about the electricity production method and its energy sources and discloses the date and location of production.
High-level radioactive waste
Spent fuel removed from a nuclear power plant is high-level radioactive waste.
Lost workday injury frequency (LWIF)
The number of injuries per million working hours, absence of one or more working day or shift excluding the day the accident happened.
Low- and intermediate-level radioactive waste
In addition to high-level radioactive waste, nuclear power plant operations also generate low- or intermediate-level radioactive waste. Similar waste is also generated when a nuclear power plant is dismantled.
A hydrocarbon compound. Natural gas consists of more than 99 per cent methane. Methane is a greenhouse gas. 
Nitrogen oxides
NO and NO2 are produced during the combustion of fuel from both the nitrogen contained in fuel and in the combustion air.
Primary energy
Unrefined, natural energy. The energy content of fuel is commonly referred to as primary energy.
The word “reject” is derived from the Latin verb “reicere” meaning “to throw back”. In the context of our sustainability report, the noun “reject” means non-recoverable refuse material from our waste sorting process.
Renewable energy certificate
The purpose of the renewable energy certificate (green certificate) system is to increase the use of renewable energy sources where it is most cost-effective. Certificates can be bought and sold and are proof that a certain amount of electricity has been produced with renewable energy sources.
Renewable energy sources
Renewable energy sources include solar, wind, hydro and bioenergy, geothermal, and wave and tidal energy. Renewable energy sources do not cause greenhouse gas emissions.
Smart grid
A grid in which electricity is transferred in the future both from the production plant to the consumer and from the consumer’s production equipment to the grid. A smart grid is a marketplace for distributed energy production and for consumers. Everything occurs in real time, the grid adapts, scales, anticipates and corrects itself using automation. Smart solutions also connect information and communications technology to the electricity infrastructure.
Specific emissions
The amount of emissions of a plant in proportion to the amount of energy produced. The specific emissions figure (for example g/kWh) indicates how effectively the emissions have been reduced.
Sulphur dioxide
A chemical compound generated in the combustion of fuels containing sulphur.
Sustainable development
Development that fulfils the needs of present generations without compromising the ability of future generations to fulfil their own needs. Sustainable development is considered to encompass economic, environmental and social dimensions.
Total recordable injury frequency (TRIF)
The number of injuries per million working hours. In addition to LWI accidents, this figure includes medical treatment cases and restricted workday cases.
United Nations’ Sustainable Development Goals (SDG)
The Sustainable Development Goals (SDGs) are objectives that have been created by the United Nations and relate to the future of international development. The Sustainable Development Goals have been set for the years 2015–2030.
Virtual power plant
In the virtual power plant, both business and private clients let their unused electricity to be used to balance volume fluctuations in electricity production. Thus, the virtual power plant creates a reserve that can be sold to a local transmission system operator (e.g. Fingrid in Finland) during peak electricity demand.


CCS = Carbon capture and storage
CDP = Carbon disclosure project
CHP = Combined heat and power production
CH4 = Methane
CO2 = Carbon dioxide
EHS = Environment, health and safety
GHG = Greenhouse gases
IEA = International Energy Agency
ILO = International Labour Organisation
INES = International nuclear event scale
LWIF = Lost workday injury frequency
NO2 = Nitrogen dioxide
N2O = Nitrous oxide
SDG = Sustainable development goals
SO2 = Sulphur dioxide
TRIF = Total recordable injury frequency


1 terawatt hour (TWh) = 1,000 gigawatt hours (GWh) = 1,000,000 megawatt hours (MWh) = 1,000,000,000 kilowatt hours (kWh)
1 terawatt hour (TWh) = 3,600 terajoules (TJ)
1 terajoule (TJ) = 278 megawatt hours (MWh)
1 petajoule (PJ) = 1000 terajoules (TJ)
1 megawatt (MW) = 1,000 kilowatts (kW) = 1,000,000 watts (W)
1 cubic metre (m3) = 1,000 litres (l)
1 normal cubic metre (Nm3) = 1 m3 of gas in normal atmospheric pressure (1.0 bar) and temperature 0 oC
1 tonne (t) = 1,000 kilograms (kg)
1 megatonne (Mt) = 1,000,000 tonnes (t) = 1,000,000,000 kilograms (kg)
1 becquerel (Bq) = 1 nuclear transformation per second
1 terabecquerel (TBq) = 1 000 gigabecquerels (GBq) = 1 000 000 000 000 becquerels