Photo – View from Stadshustornet (town hall tower), Stockholm (the capital of Sweden), September 2013.1
Sweden’s energy supply in 2016 (the most recent year of free IEA data) was admirably 24% hydro, 24% nuclear and 6% wind. The remaining 46% consisted of roughly equal shares of fossil fuels, and the combination of biofuels (i.e. vegetation) and waste. Sweden consumed a third of its total energy supply as electricity, which is 75% higher than the world average of 18%.
The increased share of nuclear energy during the 1980s resulted in rapid decarbonisation, but soon 38% of this capacity will be decommissioned. Concurrently, the share of energy from biofuels is increasing resulting in recarbonisation, despite the Swedish government and the Swedish bioenergy trade association, Svebio3 claiming this fuel to be carbon-neutral. Biofuels allow Sweden to maintain or increase its energy supply while not reporting this share of carbon emissions, as explained below. Unfortunately in 2017, 1.68 billion Euros worth of new biofuel combined heat and power projects were underway.4
Sweden’s Energy System
Sweden’s energy supply in 2016 consisted of large and roughly equal shares of energy from oil, biofuels & waste, nuclear and hydro –
The chart below compares Sweden’s energy supply with that of the world. The relatively large shares of hydro and nuclear energy in Sweden’s energy supply are admirable.
Chart 3 shows how Sweden consumed the supplied energy in chart 1 (refer to figure 1 of the introduction for an explanation of energy supply and energy consumption).
Sweden consumed a third of this energy in the form of electricity, 75% greater than the world average of about 18% in 2016.8 80% of Sweden’s electricity was generated by equal shares of nuclear and hydro energy, with most of the remainder being generated by wind and biofuels.
Sweden constructed four nuclear power stations, each consisting of multiple reactors. Interestingly, construction times for the first reactors was typically only 6 years, despite their capacities being large at 600MW to 800MW.11 12 In total 12 reactors were commissioned in Sweden, progressively between 1972 and 1985, with a total capacity reaching 11GW.13 This caused rapid and significant lowering of CO2 emissions by about a third in only five years,14 as shown in chart 4. No reactors were commissioned after 1985, and after 2020 half (i.e. 6 of the reactors or 38% of the original 11GW capacity)15 will have been decommissioned. The remaining 62% of capacity is expected to operate until at least 2040. Currently 4 of the 6 reactors to be decommissioned (22% of original capacity)16 have been shutdown permanently.
Sweden’s territorial CO2 emissions are shown below. Territorial emissions consist of emissions from fossil fuels and cement manufacture, and exclude emissions from imports, land use, land use change and forestry. Note the rapid decline during the 1980s due to increased nuclear energy supply, equating to a linear decline of -5.6%/yr.18
Sweden is a country dominated by forests. Sweden holds just under 1% of the world’s commercial forest areas, but provides 10% of the sawn timber, pulp and paper that is traded on the global market.The Swedish Forest Agency22
The final unique aspect of Sweden’s energy supply, shown in chart 1, is the relatively large 21% share of energy supply from biofuels and waste. The chart below shows the production of this energy in Sweden is about 14% waste and 84% ‘primary solid biofuels’. Solid biofuel is also known as biomass, which is simply vegetation, or biological matter that was created by photosynthesis. This term does not distinguish between slow growing biofuels such as trees, and fast growing biofuels such as grass.
About 55% of Sweden’s land area is forested,23 so it’s not surprising biofuel would feature in the country’s energy system. Unfortunately the assessment of carbon emissions from this is a mire, distorted by perverse carbon-accountancy, a lack of regulation and deceptive marketing by trade associations and biofuel companies.
Increased bioenergy use is the main reason that Sweden managed to decrease greenhouse gas emissions by 25% between 1990 and 2014, while GNP increased by 60%. Bioenergy use more than doubled during the period.Svebio, Swedish bioenergy trade association24
Note that bioenergy is term to describe energy from biofuels.
The above claim about emissions, and the recent decline in chart 4 above, may be false. There is a perception that energy from biofuels does not impact the climate, but this is not necessarily the case, as explained by a report published by Chatham House, a policy institute based in London.25 (Note that Chatham House refer to ‘solid biofuels’ as biomass).
The use of wood for electricity generation and heat in modern technologies has grown rapidly in recent years. For its supporters, it represents a relatively cheap and flexible way of supplying renewable energy, with benefits to the global climate and to forest industries. To its critics, it can release more greenhouse gas emissions into the atmosphere than the fossil fuels it replaces, and threatens the maintenance of natural forests and the biodiversity that depends on them. Like the debate around transport biofuels a few years ago, this has become a highly contested subject with very few areas of consensus. This paper provides an overview of the debate around the impact of wood energy on the global climate, and aims to reach conclusions for policymakers on the appropriate way forward.
Although there are alternatives to the use of wood for biomass power and heat, including organic waste, agricultural residues and energy crops, they tend to be less energy-dense, more expensive and more difficult to collect and transport. Wood – and particularly wood pellets, now the dominant solid biomass commodity on world markets – is therefore likely to remain the biomass fuel of choice for some time.Woody Biomass for Power and Heat, Impacts on the Global Climate.26
Chatham House claim the misconception that biofuel energy does not impact the climate is due to two assumptions (all emphasis below has been added) –
Biomass is classified as a source of renewable energy in national policy frameworks, benefiting from financial and regulatory support on the grounds that, like other renewables, it is a carbon-neutral energy source. It is not carbon-neutral at the point of combustion, however; if biomass is burnt in the presence of oxygen, it produces carbon dioxide. The argument is increasingly made that its use can have negative impacts on the global climate. This classification as carbon-neutral derives from either or both of two assumptions. First, that biomass emissions are part of a natural cycle in which forest growth absorbs the carbon emitted by burning wood for energy. Second, that biomass emissions are accounted for in the land-use sector, and not in the energy sector, under international rules for greenhouse gas emissions.Woody Biomass for Power and Heat, Impacts on the Global Climate.26
The first assumption is that woody biomass emissions are part of a natural cycle in which, over time, forest growth balances the carbon emitted by burning wood for energy. In fact, since in general woody biomass is less energy dense than fossil fuels, and contains higher quantities of moisture and less hydrogen, at the point of combustion burning wood for energy usually emits more greenhouse gases per unit of energy produced than fossil fuels. The impact on the climate will also depend on the supply-chain emissions from harvesting, collecting, processing and transport. Estimates of these factors vary widely but they can be very significant, particularly where methane emissions from wood storage are taken into account. Overall, while some instances of biomass energy use may result in lower life-cycle emissions than fossil fuels, in most circumstances, comparing technologies of similar ages, the use of woody biomass for energy will release higher levels of emissions than coal and considerably higher levels than gas.Woody Biomass for Power and Heat, Impacts on the Global Climate.26
The report, as well as another by Columbia University,27 explains this assumption in greater detail –
It is often argued that biomass emissions should be considered to be zero at the point of combustion because carbon has been absorbed during the growth of the trees, either because the timber is harvested from a sustainably managed forest, or because forest area as a whole is increasing (at least in Europe and North America). The methodology specified in the 2009 EU Renewable Energy Directive and many national policy frameworks for calculating emissions from biomass only considers supply-chain emissions, counting combustion emissions as zero.
These arguments are not credible. They ignore what happens to the wood after it is harvested (emissions will be different if the wood is burnt or made into products) and the carbon sequestration forgone from harvesting the trees that if left unharvested would have continued to grow and absorb carbon. The evidence suggests that this is true even for mature trees, which absorb carbon at a faster rate than young trees. Furthermore, even if the forest is replanted, soil carbon losses during harvesting may delay a forest’s return to its status as a carbon sink for 10–20 years.
Another argument for a positive impact of burning woody biomass is if the forest area expands as a direct result of harvesting wood for energy, and if the additional growth exceeds the emissions from combustion of biomass. Various models have predicted that this could be the case, but it is not yet clear that this phenomenon is actually being observed. For example, the timberland area in the southeast of the US (where most US wood pellet mills supplying the EU are found) does not appear to be increasing significantly. In any case, the models that predict this often assume that old-growth forests are replaced by fast-growing plantations, which in itself leads to higher carbon emissions and negative impacts on biodiversity.
The carbon payback approach argues that, while they are higher than when using fossil fuels, carbon emissions from burning woody biomass can be absorbed by forest regrowth. The time this takes – the carbon payback period before which carbon emissions return to the level they would have been at if fossil fuels had been used – is of crucial importance. The many attempts that have been made to estimate carbon payback periods suggest that these vary substantially, from less than 20 years to many decades and in some cases even centuries.Woody Biomass for Power and Heat, Impacts on the Global Climate.26
Note the above states that the time taken for carbon emissions from combustion of woody-biomass to be equal to that from a coal or gas power station can range from less than 20 years to decades or centuries. For such energy to be carbon-neutral would take even longer. Furthermore –
Some have argued that the length of the carbon payback period does not matter as long as all emissions are eventually absorbed. This ignores the potential impact in the short term on climate tipping points (a concept for which there is some evidence) and on the world’s ability to meet the target set in the 2015 Paris Agreement to limit temperature increase to 1.5°C above pre-industrial levels, which requires greenhouse gas emissions to peak in the near term. This suggests that only biomass energy with the shortest carbon payback periods should be eligible for financial and regulatory support.Woody Biomass for Power and Heat, Impacts on the Global Climate.26
The second assumption that creates the misconception that energy from biofuels does not impact the climate is the potentially mistaken understanding that carbon emissions from biofuel energy are tallied for a given country, as explained by Chatham House –
In order to avoid double-counting emissions from biomass energy within the energy sector (when the biomass is burned) and the land-use sector (when the biomass is harvested), the rules provide that emissions should be reported within the land-use sector only.
While this approach makes sense for reporting, it has resulted in significant gaps in the context of accounting – measuring emissions levels against countries’ targets under the Kyoto Protocol (or, potentially, the Paris Agreement), largely deriving from the different forest-management reference levels that parties have been permitted to adopt.
The problem of ‘missing’, or unaccounted-for, emissions arises when a country using biomass for energy:
Imports it from a country outside the accounting framework – such as the US, Canada or Russia, all significant exporters of woody biomass that do not account for greenhouse gas emissions under the second commitment period of the Kyoto Protocol;
Accounts for its biomass emissions using a historical forest-management reference level that includes higher levels of biomass-related emissions than in the present; or
Accounts for its biomass-related emissions using a business-as-usual forest-management reference level that includes, explicitly or implicitly, anticipated emissions from biomass energy (since the associated emissions built in to the projection will not count against its national target).Woody Biomass for Power and Heat, Impacts on the Global Climate.26
Either of the later two arrangements above may apply to Sweden. Interestingly –
Neither the US nor Japan account for emissions from their land-use sectors under the Kyoto Protocol, while Germany accounts against a business-as-usual projection that does not explicitly include bioenergy policies, and France uses a business-as-usual projection that includes bioenergy demand from policies up to, but not including, the EU Renewable Energy Directive. Woody biomass emissions from all these countries, therefore, have the potential to go unaccounted for.Woody Biomass for Power and Heat, Impacts on the Global Climate.26
How then should Sweden’s energy supply be represented? The most precautionary manner would be the righthand most chart below –
Sweden’s energy supply over time is shown below, followed by the same data in stacked form. The rise of biofuels and waste, and wind is obvious, as well as the decline of oil, mainly attributable to reduced consumption by industry as shown further below.
Sweden’s energy supply by share is shown below. While the low share of fossil fuels, at only 25% in 2016 is impressive, this is overshadowed by the 21% share of biofuels and waste –
The tables below show Sweden’s energy supply in detail for years 2012 and 2016. Table (d) shows the cumulative energy supplied during 2012 to 2016. Hydro and nuclear supplied roughly equal quantities of energy, and that quantity equalled fossil fuels. Biofuels, waste and wind combined also supplied an equal share. All other supplies were negligible.
Table 2 details Sweden’s energy supply in 1990 and 2016 –
A measure of decarbonisation is the carbon intensity of total primary energy supply, which is a measure of the quantity of carbon emitted for every unit of energy (i.e. Joule) supplied by an energy system. While chart 10 shows Sweden’s reported carbon intensity to be very low, this is because biofuel and waste emissions are not accounted for in the energy sector, if at all. The factual carbon intensity of Sweden’s energy system is unknown.
As shown in figure 1 of the introduction, the forms and quantities of energy we consume (known as ‘total final consumption’ or TFC) differs from that which is supplied. For example, some energy supplied by coal is converted and consumed as electricity, and the rest is instead combusted and consumed in industrial applications (e.g. steel manufacture) and domestic applications (e.g. cooking). The calculation of total final consumption allows us to profile how economies annually use the energy supplied.
Sweden’s energy consumption in 2016 was shown in chart 2, and is shown over time below. Sweden mainly consumes supplied energy as oil, electricity, district heat, and by in-situ combustion of biofuels and waste. (For clarity, forms of energy with zero value have been excluded from the following charts).
Sweden’s electricity generation over time is shown below, dominated by nuclear and hydro. Electricity generated by wind is similar to that by biofuels. Chart 2 above shows the share of each for year 2016.
Consumption by the industrial sector is shown below. This is Sweden’s greatest consumer of biofuels and waste (rather than distributed electricity or distributed heat). The total energy consumption by industry in 2016 was about 10% less than in 1990, with a significant peak during the 1990s.
Chart 14 shows the consumption of energy by Sweden’s transport sector, and includes domestic aviation. While this is dominated by oil, which is typical, the rise of liquid biofuels is notable.
In 2017 biofuels, mainly biodiesel, accounted for 20% of all road transport fuels in Sweden.29
As explained above, energy from biofuel is not necessarily carbon-neutral; energy supplied by woody-biomass is not, but energy from fast growing crops may be.
The rapid growth of biofuels in recent years is mainly attributed to the increased use of hydrotreated vegetable oil (HVO) renewable diesel fuels, which are produced from various bio-based raw materials.Bioenergy International, 2017 another record year for biofuels in Sweden.29
There is insufficient information shown here to determine the impact on carbon emissions due to Sweden’s increased share of biofuels in their transport sector; the proportion obtained from woody biomass would need to be known.
Finally, shown below is the consumption of energy by the residential, commercial, agricultural and fishing sectors combined. The rise in district heating is prominent.
While Sweden has undertaken significant efforts to decarbonise its energy supply, the share of energy from biofuels and waste has grown significantly, seemingly without regard to the consequential carbon emissions. The Chatham House report, Woody Biomass for Power and Heat: Impacts on the Global Climate,30 makes detailed recommendations that Sweden’s government could utilise to produce honest and transparent accountancy of territorial carbon emissions, and then perhaps factual decarbonisation.
- https://commons.wikimedia.org/wiki/File:Stockholm_8721-B_(9870833193).jpg, photo credit: Bengt Nyman from Vaxholm, Sweden (CC BY 2.0)
- https://commons.wikimedia.org/wiki/File:EU_location_SWE.png, photo credit: David Liuzzo (CC BY-SA 4.0
- For World energy supply see https://www.worldenergydata.org/world-energy-supply/
- Chart 1, https://www.worldenergydata.org/world-energy-consumption/
- 615 + 615 + 865 + 900 + 1070 + 1120 + 1450 + 494 + 664 + 984 + 1120 + 1170 = 11,067MW, https://en.wikipedia.org/wiki/Nuclear_power_in_Sweden
- Territorial emissions in 1979 = 85MtCO2), 1984 = 57MtCO2), (57 – 85)/85 = -33% over 5 years
- (615 + 615+865 + 900+ 494+ 664) / 11,067 = 38%
- (615 + 615 + 494 + 664) / 11,067
- https://commons.wikimedia.org/wiki/File:Forsmark3.jpg, photo credit: robin-root (CC BY-SA 2.0)
- Territorial emissions in 1979 = 85MtCO2, 1984 = 57MtCO2 (ref: http://www.globalcarbonatlas.org/en/CO2-emissions), (57 – 85)/(1984 – 1979) = -5.6%/yr of original amount.
- https://en.wikipedia.org/wiki/File:Vy_mot_Stora_Sjöfallet_från_Saltoluokta.jpg, photo credit: STF Saltoluokta Fjällstation
- https://en.wikipedia.org/wiki/Forests_of_Sweden, https://www.sveaskog.se/en/forestry-the-swedish-way/short-facts/brief-facts-1/
- Is Biomass Really Renewable? by Renee Cho, Earth Institute, Columbia University, blogs.ei.columbia.edu/2011/08/18/is-biomass-really-renewable/
- https://commons.wikimedia.org/wiki/File:FIL2938.JPG, photo credit: Mattias Hedström (CC BY-SA 2.5)