Energy [R]evolution 2010—a sustainable world energy outlook

The MESAP/PlaNet model

The simulation model PlaNet of the energy and environmental planning package MESAP (2008) has been created for long-term strategic planning on a national, regional or local level. PlaNet consists of two independent modules: a flow calculation module, balancing the flows of commodities of an energy demand and supply model, a cost calculation module for the calculation of the corresponding macroeconomical costs. Energy system analyses with PlaNet are carried out in two sequential steps: first the energy and material flows are determined; then based on the results of the flow calculation, the costs of this energy system are calculated.

The PlaNet flow calculation uses a set of linear equations, which can be solved sequentially. In a simulation model, the user specifies the activities or drivers of demand represented as quantities of a commodity, for example the population or the GDP. With the help of intensities (ratios between flows) like electricity consumption per person, the demand for energy services or the final energy demand can be determined. If a commodity is produced by more than one process, market shares for these processes have to be specified. The market shares define the output of a process. The input into this process will be calculated with process efficiency. This schematic allows the integrated calculation of energy flows from primary energy sources to demand drivers. The cost calculations are based on the results of the flow calculation. The estimates of the future development of population, GDP and energy intensities used in this study are presented in detail below (“Key drivers for energy demand” section).

A ten-region global energy system model implemented in the MESAP/PlaNet environment (MESAP 2008) is used for simulating global energy supply strategies. The ten regions correspond to the world regions as specified by the IEA’s World Energy Outlook 2009 (Africa, China, India, Latin America, Middle East, OECD Europe, OECD North America, OECD Pacific, Other Developing Asia, Transition Economies) (IEA 2009a). Model calibration for the base year 2007 is based on IEA energy statistics (IEA 2009b, c).

The scenarios

Three scenarios up to the year 2050 are outlined in this research: a Reference scenario, a basic Energy [R]evolution scenario with a target to reduce energy related CO₂ emissions by 50%, from their 1990 levels, and an advanced Energy [R]evolution version which envisages a fall of more than 80% in CO₂ by 2050.

The Reference scenario is based on the reference scenario in the International Energy Agency’s 2009 World Energy Outlook (IEA 2009a). This only takes existing international energy and environmental policies into account. The Reference scenario does not consider additional policies to reduce greenhouse gas emissions. As the IEA’s projection only covers a time horizon up to 2030, it has been extended by extrapolating its key macroeconomic and energy indicators forward to 2050. Long-term projections of economic developments are only indicative and are used to project future development of the global energy demand and are by no means forecasts. The Reference scenario provides a baseline for comparison with both Energy [R]evolution scenarios. Compared to the previous (2007) IEA projections (IEA 2007), WEO 2009 assumes a slightly lower average annual growth rate of world Gross Domestic Product (GDP; 3.1%, instead of 3.6% over the period 2007–2030). At the same time, it expects global final energy consumption in 2030 to be 6% lower than in the WEO 2007 report. China and India are expected to grow faster than other regions, followed by the Other Developing Asia group of countries, Africa and the Transition Economies (mainly the former Soviet Union). The OECD share of global purchasing power parity (PPP) adjusted GDP is expected decrease from 55% in 2007 to 29% by 2050.

The Energy [R]evolution scenario has a key target of 50% renewables of the final energy consumption by 2050. A second objective is the global phasing out of nuclear energy. To achieve these goals, the scenario is characterised by significant efforts to fully exploit the large potential for energy efficiency. At the same time, all cost-effective sustainable renewable energy¹ sources are used for heat and electricity generation, as well as the production of bio fuels. The general framework parameters for population and GDP growth remain unchanged from the Reference scenario.

The Advanced Energy [R]evolution scenario takes a much more radical approach and aims to reduce global energy related CO₂ emissions by more than 80% in 2050, based on 1990 levels, to increase the likelihood of limiting warming to less than a +2° increase of the global average temperature. In order to achieve this even more ambitious reduction of CO₂ emissions, the advanced scenario assumes much shorter lifetimes for coal-fired power plants—20 years instead of 40 years. The shorter lifetime for coal power plants enables a larger deployment of renewable energy sources and the annual growth rates of renewable energy sources, especially solar photovoltaic, wind and concentrating solar power plants, have therefore been increased.

The advanced scenario also uses the general framework parameters of population and economic growth, as well as most of the energy efficiency roadmap from the basic Energy [R]evolution (E[R]) scenario. In the transport sector, however, the advanced E[R] scenario has a final energy demand 15% to 20% lower in 2050 compared to the basic E[R] scenario. This is due to a combination of increased use of public transport and a faster uptake of efficient combustion vehicles and—after 2025—a larger share of electric vehicles. Within the heating sector, there is a faster expansion of combined heat and power generation (CHP) in the industry sector, more electricity for process heat and a faster growth of solar and geothermal heating systems. Combined with a larger share of electric drives in the transport sector, this results in a higher overall demand for power. Even so, the overall global electricity demand in the advanced Energy [R]evolution scenario is still lower than in the Reference scenario. In the advanced scenario, the latest market development projections of the renewable industry have been calculated for all sectors. More electric and hydrogen vehicles, combined with the faster implementation of smart grids and expanding super grids (about 10 years ahead of the basic E[R] scenario) allows a higher share of fluctuating renewable power generation (photovoltaic and wind). The threshold of a 40% proportion of renewables in global primary energy supply is therefore passed just after 2030 (also 10 years ahead of the basic E[R] scenario). By contrast, the quantity of biomass used for energy purposes and large hydro power remain approximately the same in both Energy [R]evolution scenarios, for sustainability reasons.

Both the basic and the advanced Energy [R]evolution scenarios have been developed in a backcasting process.² The CO₂ emission target has been defined on the basis of the IPCC 4th assessment report, category 1 scenario (IPCC 2007) to restrict the increase in global mean temperatures under +2°C with a required CO₂ reduction of −85% to −50% by 2050. Therefore, the main target is to reduce global CO₂ emissions to 10 Gt/a by 2050 in the basic Energy [R]evolution scenario and 3.7 Gt/a in the advanced Energy [R]evolution scenario, thus limiting global average temperature increase well below 2°C and preventing dangerous anthropogenic interference with the climate system (Hansen et al. 2008, see also the United Nations Framework Convention on Climate Change, Article 2, UNFCCC 1992). As the authors do not consider nuclear energy as an option that supports the transition towards a sustainable energy supply system, a second constraint is the phasing out of nuclear power plants until 2050.

Energy demand projections

In order to estimate the global and regional energy efficiency potential, the Dutch institute Ecofys developed energy demand scenarios for the Greenpeace Energy [R]evolution analysis in 2008 (Graus and Blomen 2008). These scenarios cover energy demand over the period 2005 to 2050 for ten world regions. Two low energy demand scenarios for energy efficiency improvements have been defined. The first is based on the best technical energy efficiency potentials and is called “Technical”. The second energy efficiency scenario is based on more moderate energy savings, taking into account implementation constraints in terms of costs and other barriers and is called “Revolution”. The technical potential is defined as the energy use that can be reduced by implementing established technical measures, in comparison to the level of energy use in a reference scenario, where current trends continue and no large changes take place in the production and consumption structure of the economy. The technical potential scenario assumes that measures can be implemented after 2010 and that equipment or installations are replaced at the end of their lifetime by state-of-the-art equipment. However, the Revolution scenario assumes that only a fraction of the technical energy efficiency potential can be implemented. This approach takes into account barriers for implementing technical measures for energy efficiency improvements, such as costs. Energy demand in both the basic and the advanced Energy [R]evolution scenarios is based on this second, more conservative “Revolution” scenario. The main results of the “Revolution” scenario are summarised below.

For the 2010 update of the Energy [R]evolution scenario, including the advanced version, the Graus and Blomen (2008) analysis has been reconfigured using the latest IEA statistics from World Energy Outlook 2009 (IEA 2009a). The WEO 2009 edition has a lower global final energy demand in 2030 in comparison to the 2007 edition; 438 EJ in comparison to 478 EJ (including non-energy use). The difference is mainly caused by lower GDP growth rates due to the recent financial and economic crisis, leading to a 14% lower global GDP in 2030 in comparison to the 2007 edition. In addition, an increased share of electric vehicles in the advanced scenario results in a lower final energy demand required to meet the same level of transport activity.

Key drivers for energy demand

Technical potential for energy efficiency improvement

After defining energy intensities of the Reference scenario, technical potentials for energy efficiency improvement are estimated. In this step, a list is drawn up of energy savings options taken into account per sector. After that, the technical energy savings potential is estimated per measure. The technical potentials are based on:

• Current best practice technologies

• Emerging technologies that are currently under development

• Continuous innovation in the field of energy efficiency, leading to new technologies in the future

The key assumptions for calculating technical potential are:

• Measures can be implemented after 2010

• Equipment is replaced at the end of the (economic) lifetime of equipment by state-of-the-art equipment

This study aims at calculating energy efficiency improvement by developing indicators for energy-intensity per sector and where possible by subsector.

The main energy consuming sectors are the industry and transport sectors, as well as “other sectors”, (residential sectors, services and agriculture; Graus and Blomen 2008) the subsector energy use and the selection of the measures per sector are discussed and shown in detail. Options are selected, which are expected to result in a substantial reduction of energy demand before 2050.

In the Reference scenario, total global energy demand is expected to increase from 305 EJ in 2007 to 352 EJ in 2050. The growth in the transport sector is projected to be the largest, with energy demand expected to grow from 82 EJ in 2007 to 158 EJ by 2050 (see Table 1). Demand from “other sectors” is expected to grow the least, from 124 EJ in 2007 to 198 EJ by 2050. Under the (basic) Energy [R]evolution scenario, however, growth in overall final energy demand can be limited to an increase of 12% up to 2050 in comparison to the 2007 level (341 EJ in 2050), whilst taking into account implementation constraints in terms of costs and other barriers. The increase of the energy demand in the transport sector is very small, while in the industry and other sectors, final energy demand increases by ca. 17% (resp. 15%) between 2007 and 2050.

Table 1

Change in global final energy demand by 2050 in comparison to 2005 level

Sector	Energy [R]evolution		Reference
	2007	2050	2007	2050
Industry	99 EJ	116 EJ	99 EJ	176 EJ
Transport	82 EJ	84 EJ	82 EJ	158 EJ
Buildings and others	124 EJ	142 EJ	124 EJ	198 EJ
Total	305 EJ	341 EJ	305 EJ	532 EJ

Figure 1 shows the potential for energy efficiency measurements for the industry, transport and other sectors in 2050 for the different world regions, i.e. the difference between the energy demand in these sectors in 2050 in the Reference scenario and the respective demand in the basic E[R] scenario, normalised to the 2005 level of total energy demand in each world region. Furthermore, the remaining total energy demand in 2050 in the basic E[R] scenario (relative to 2005 levels) is shown.

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The technical savings potential up to 2050 from all the measures described in (Graus and Blomen 2008) is summarised in Table 2. Since it was not clear what assumptions the IEA WEO Reference scenario was based on, they have assumed an efficiency improvement of 1% per year. Electricity use in the “other” sector was assumed to decline at the same rate as residential use (lighting, appliances, cold appliances, computers/servers and air conditioning). They have assumed a minimum energy efficiency improvement of 1.2% in the Technical scenario and 1.1% in their Revolution scenario, including autonomous improvements. For services and agriculture, they have assumed the same percentage savings potential as for the household sector all aggregated in “other sectors”. The new Reference scenario based on WEO 2009 data now includes a lower level of energy demand in the residential sector. Therefore the savings used in the new Energy [R]evolution scenarios are lower than the figures shown in Table 2. The resulting final energy demand reduction for the Energy [R]evolution scenarios compared to the Reference scenario is shown in Table 3 for each world region.

Table 2

Technical savings potential by 2050 for different types of energy use n the buildings sector

	Heating—new	Heating—retrofit	Standby	Lighting	Appliances	Cold appliances	Air conditioning	Computer/server	Other
OECD Europe	72	50	82	68	70	77	70	70	71
OECD N.-Am.	59	41		48					67
OECD Pac.	38	26		56					69
Transition Ec.	56	39		76					73
China	43			20					61
India				76					73
Other dev. Asia
Middle East
Latin America
Africa

Table 3

Reduction of final energy demand in other sectors between 2005 and 2050

	Other sectors electricity	Other sectors final energy other than electricity
OECD Europe	−46%	−36%
OECD North America	−42%	−28%
OECD Pacific	−33%	−28%
Transition economies	−45%	−36%
China	−27%	−23%
India	−12%	−29%
Other developing Asia	−39%	−15%
Middle America	−36%	−15%
Latin America	−16%	−18%
Africa	−6%	−7%

Estimates of the potential of renewable energy sources

Worldwide renewable energy resources exceed by several times current energy demand. The availability of renewable energy sources however differ between world regions (UBA 2009). The supply with energy from renewable sources in the both the basic and the advanced Energy [R]evolution scenarios is constrained by estimates of renewable energy potentials by world region and technology (REN21 (2008); Hoogwijk and Graus (2008) and UBA (2009)). Assessments of the global technical potential vary significantly up to 15,857 EJ/a (UBA 2009). This meta study performed by the DLR, Wuppertal Institute and Ecofys, commissioned by the German Federal Environment Agency analysed ten major studies of global and regional potentials by organisations such as the United Nations Development Programme and a range of academic institutions. Each of the major renewable energy sources was assessed, with special attention paid to the effect of environmental constraints on their overall potential. The study provides data for the years 2020, 2030 and 2050. The potential for energy supply from biomass in each world region was addressed separately from the results in the UBA (2009) study (see below).

Global potentials of energy crops

Besides the utilisation of biomass from residues, the production of energy crops in agricultural production systems is of controversial. Therefore, the technical potentials of energy crops were calculated assuming that the demand for food takes priority. In a first step, different scenarios for the demand of arable land and grassland for food production were calculated for each of 133 countries.

• BAU scenario: Agricultural conditions existing at present time also apply for the future.

• Basic scenario: No forest clearing; reduced use of fallow areas for agriculture

• Sub 1 scenario: Basic scenario + ecological area expanded, followed by reduced yield level

• Sub 2 scenario: Basic scenario + food consumption is reduced for industrialised countries

• Sub 3 scenario: combination of Sub 1 and 2 scenarios

The needs and surpluses of agricultural areas are balanced between the countries of the groups EU-27, other European countries, North America, Central America, South America, Oceania, Asia and Africa to estimate the area available for the cultivation of energy crops in each world region. In a next step, the surpluses of agricultural area in each world region are classified as arable land and grassland. On grassland hay and grass silage are produced, on arable land fodder silage³ and short rotation coppice⁴ (SRC) are cultivated. Silage of green fodder and grass are assumed for biogas production, wood from SRC and hay from grasslands are assumed for the production of heat, electricity and synthetic fuels (BtL⁵ or ethanol from lignocelluloses).⁶ Country specific yield developments are taken into consideration.

As a result, the global biomass potential from energy crops in 2050 was estimated to range from 6 EJ in the Sub 1 scenario to 97 EJ in the BAU scenario (see Fig. 2). In comparison to the BAU scenario, potentials decrease clearly in the Basic and Sub 1 scenario, and the lowest potentials exist in the Sub 1 scenario. The considerable higher demand of agricultural area in the Sub 1 scenario compared to the Basic and the BAU scenario is due to an ecological orientated agriculture with less fertilizer and less pesticide and therefore lower specific yields. In the Sub 2 scenario, considerable higher energy crop potentials can be released by changing the human food pattern, reducing meat consumption and consequently, the area necessary for fodder production. Also in the Sub 3 scenario, considerable potentials can be realized, in most cases even higher than in the BAU scenario. The most important country for the differences between the scenarios in 2050 is Brazil. In the BAU scenario, big agricultural areas are released by deforestation in Brazil, whereas in the Basic and Sub 1 scenario, this deforestation does not occur anymore. Consequently, no additional agricultural area for energy crops is available in Brazil in these two scenarios. In contrast high potentials are available in the Sub 2 scenario as a consequence of the reduced meat consumption of the Brazilian. Because of high population and low quantity of agricultural area, no area surpluses for energy crop production are available in Central America, Asia and Africa. However, the EU, North America and Australia have relatively stable potentials.

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The Basic and Sub 3 scenario are of particular importance, since the Basic scenario would be the “minimum solution” for future agriculture. The Sub 3 scenario demonstrates the development of an ecological orientated agriculture. But such a development is only realistic, if the eating behaviour changes. Otherwise, the higher demand of food crops from an increasing world population cannot be compensated. The results of the calculation show that the availability of biomass resources is driven by different factors (as evident in the boundary conditions set in the different scenarios above), which do not only affect the global food situation but also the conservation of natural forests and other biospheres. So, the assessment of future biomass potentials is the starting point for the discussion about the integration of bio energy into a renewable energy system.

Economic boundary conditions

To implement the Energy [R]evolution pathways, an assessment of costs and benefits for society is essential. For this study, we focused on the costs of the power sector, calculating power generation costs as well as necessary investments and fuel costs for each scenario. The main assumptions for the cost calculation are presented in the following: Assumptions for heat and transport prices require a much more detailed approach for each region, thus were not included in the economic assessment.