What do you know about energy ?

Energy and the development of modern societies

Energy played a critical role in the development of Human civilisations, from the discovery of fire 250 000 years ago to the introduction of steam engines and electricity.

The invention of the steam engine by James Watt in 1769 marked the beginning of a new era. Though biomass, and notably wood, remained the main source of energy until the middle of the XIX century, it was then rapidly replaced with a far more efficient and less costly resource, coal. Then came oil, which consumption grew exponentially with the introduction of modern means of transportation (maritime, vehicles and later on airplanes), gas and uranium for nuclear electricity.

Share of energy sources in the global energy mix since the mid XIXth century

- International Institute for Applied Systems Analysis at Cambridge University Press (2012) – From Global Energy Assessment: Towards a sustainable future
- International Institute for Applied Systems Analysis at Cambridge University Press (2012) – From Global Energy Assessment: Towards a sustainable future

In the meantime, the introduction of electricity and its rapid spread in the XXth century revolutionized the energy sector and conditioned the development of service-based modern economies. With its numerous advantages (e.g. in terms of transportation or distribution), electricity is now common for all sorts of uses: lighting, heat and cold production, transports, Industry, etc. It enabled important progresses in a wide range of domains (including health and education) and launched a new era based on information and communication technologies.

These successive energy transitions conditioned the development of modern societies as we know today. And the growth in demand seems limitless, spurred on by demographic and economic factors. But while this growth came historically from industrialized economies, the emerging world (at its head China, South Africa, India or Brazil) is now taking the lead (figure below).

Primary energy consumption per region, in Million tons of oil equivalent

source IEA, key World energy statistics
source IEA, key World energy statistics

A vital asset in a world with limited resources

Energy is present in all aspects of our life and activities, whether it is in the residential, commercial, Industrial, Transport and Agricultural sectors, in cities, in buildings for providing basic needs such as heating and cooking, etc.

Projections from BP in “Energy Outlook 2035” show that the Industry will stay on top of all sectors and account for 13% of the rise in energy consumption by 2035. Other sectors (mainly residential sector and agriculture) will also grow at a steady rate in the near future, as shown in the figure below.

Forecast of the energy consumption by sector until 2035 (in billion toe)

According to BP’s Energy outlook 2035

But this growth does not go without consequences: the majority of energy demand (over 85%) is still provided by fossil fuels, namely coal, gas and oil. Not only are these non-renewable, i.e. their consumption is leading to a rapid depletion of available resources, but they are also polluting and the sources of massive greenhouse gases emissions (Figure below), at the origin of global warming and climate change.

Source International Panel on Climate Change
Source International Panel on Climate Change

As scientific evidences demonstrate, there is now little doubt that climate change is one of the biggest challenges faced in Human history. International negotiations have been ongoing for over two decades and an agreement was reached during the 21st Conference of Parties of the United Nations Framework Convention on Climate Change in Paris, in December 2015 (COP21). In this agreement, the international community sets itself the objective of limiting global warming well below 2°C by 2100; concretely, this would require to leave at least 2/3 of current fossil fuels reserves unexploited.

The path towards energy transition: the necessity to redefine our consumption patterns

Any activity (or any work) requires a certain amount of energy, which can take many forms: chemical, mechanical, thermal or electrical. In practice, the energy that we end up using rarely arrives in the same forms as it was originally: it went through one or several conversions. For example, in a steam engine, the fuel is burnt, releasing thermal energy which is then transformed into mechanical energy using steam.

  • Primary energy

Refers to energy sources as they are found in nature: natural gas; crude oil; biomass; solar radiation; energy from wind or water flow; etc.

  • Secondary energy

Refers to the energy obtained following the conversion of primary energy into energy that can be used, which must then be transported to consumers.

  • Final energy

Refers to the energy available to consumers. For example, it can be the gasoline that you use for your car, or the electricity or gas that you use at home or at the office.

  • Useful energy

Refers to the actual amount of energy that is used to provide the expected service. The difference between final energy and useful energy depends on the device’s performance

Losses may occur at the various stages of the chain (see below).

Energy losses between primary energy and useful energy


Coming back to energy transition, the priority for European citizens is not only to support the development of renewable energy technologies but also, and first of all, to reduce our demand for primary energy through:

  • Limiting our demand for useful energy: this is called energy conservation and depends on our consumption patterns and behaviours;
  • Reducing losses throughout the chain, i.e., losses linked to processing, production, transportation and use of energy. This is called ‘energy efficiency’ and depend much on technological progresses and investments in adequate infrastructures.

Energy conservation remains the priority and involves cutting energy demand by reducing wastage and overconsumption – such savings can often be done quickly at no or low cost (this is often called the “low hanging fruit”).

Reducing all unnecessary consumption seems logical but the distinction between essential and superfluous needs is always subjective and highly dependent on one’s context and lifestyle. To illustrate this issue, in urban areas, the need for a car can somehow be less relevant than in rural areas where no efficient public transports exist. But whereas it will be up to anyone’s judgment, questioning the essential and the superfluous is still necessary. To this extent, in its manifesto, the NGO négaWatt for example proposes to adapt the regulation based on the following energy needs ranking (see Figure below).

The energy requirements and their regulation

source Manifesto NégaWatt, 2012

Energy conservation

Beyond that and whatever the regulation, each one of us should question its own behaviours when it comes to consuming energy: is this vital? Where can I reduce my consumption? Do I waste energy in my daily habits? For example, do I leave the windows opened when the heater is on?

This approach should also include the energy used indirectly to produce the goods and services we consume. The adoption of informed and conscious behaviours is key to sustainability, especially in industrialized countries where consumption per capita remains well above world average. In this context, the project C4ET set the ambitious objectives not only to raise awareness about these issues, but also to build a path towards responsible consumption patterns.

Energy Efficiency

Unlike energy conservation which focuses on reducing demand for energy services, energy efficiency seeks to reduce the amount of energy needed to provide an equivalent level of service.

To achieve this, it is necessary to minimize the losses throughout the energy chain, from top to bottom. This means reducing losses in production, transportation, processes and improve the efficiency of equipment. As a citizen, this would imply for example to have adequate housing (e.g. insulation to avoid thermal losses), efficient appliances (Tvs, washing machines, etc.), and lighting, etc.

In order to stimulate energy efficiency, various political tools have been used:

  • Regulation and standards
  • Voluntary agreements
  • Tax and financial incentives
  • Information on good practices and dissemination
  • Labels

It should be recalled here that energy efficiency is complementary to energy conservation: energy-efficient buildings will only be truly beneficial if its users also adopt relevant behaviours. Similarly, the development of more efficient devices and equipment will not have the expected effect if, in parallel, buying decisions are not geared towards less energy consuming solutions.  Here again, raising awareness and educate citizens, along with making clear information available to assist their choices, are of critical importance.

Renewable energy

The third step of the energy transition will be to develop low-carbon, environmental-friendly, economic and resilient resources, enabling all human beings to have access to modern energy services. In the last decade or so, renewable energy have become more and more competitive – to this extent, it should be noted that incentives and subventions for fossil fuels at global level are still well above the ones for renewables. Many technologies have proven their viability (technical and economic) and generate positive externalities in terms of energy security or sustainable employment, for example.

  • Solar energy

This includes both electricity production (photovoltaic panels, solar concentration panels) and thermal production (solar panels). This sector is now well developed and has a high potential for scaling up, in Europe but also in developing countries where the resource is abundant.

  • Wind power

Inland or offshore wind turbines can be used to produce electricity. The resource also made its proofs despite some concerns about fluctuations in production. As for solar energy, wind energy dissemination potential is high.

  • Hydro power

Hydro power, which uses the force of water flows to produce electricity through a turbine and generator, remain the main source of renewable energy production in the world: according to REN21 Renewable 2015 Global Status report, it accounted in 2013 for 3.9% of global energy consumption. The potential for scaling up such technologies is also important, though some environmental and economic issues related to hydroelectric dams were raised. These include impacts on ecosystems, displacement of population, impacts on water flows for countries that are located downstream (for example China is building dams on the Mekong River, impacting agriculture and lifestyles in Vietnam or Cambodia)

  • Geothermal energy

Geothermal energy is based on the exploitation of natural heat in the earth’s subsurface. It can be more costly to develop and is available only in specific locations where there is important geothermal activity.

  • Marine energies

This sector includes a wide range of technologies and exploitation of tide energy, waves’ energy, water thermal energy (due to the difference of temperature between surface waters and deep waters), ocean currents, and osmotic energy (related to the difference in salinity between freshwater and salt water).

  • Modern biomass

Modern biomass defines the organic fuels that may come from solid (wood, straw) liquid (biofuels) or gaseous (biogas) materials, including organic waste. Unlike traditional biomass, mainly used for heating and cooking needs in developing countries, with low efficiency and negative health impacts, modern biomass refer to efficient, well-designed and clean technologies. Important note though: the definition of ‘modern biomass’ as a renewable resource presupposes that it comes from resources managed in a sustainable way.

A mix of these solutions should provide for the energy needs that can’t be reduced through conservation and efficiency, and enable the development of more resilient low carbon societies. Europe is aware of the challenge: the European Commission set itself the objective of a 27% share of renewables in the energy mix by 2030, along with a 27% improvement in energy efficiency compared to 1990 levels.

Keeping on going in the path we are now is unsustainable and significant changes are needed. But seeing the energy transition only as a necessity imposed by climate issues and depletion of resources would be wrong: it is also an historic opportunity to redefine our development models and consumption and production patterns, with benefits that are not only environmental but also economic and social.

©2017 C4ET 

This project has been funded with support from the European Commission.
This website reflects the views only of the author, and the Commission cannot be held responsible for any use 
which may be made of the information contained therein.

Project code: 2015-1-FR01-KA204-015349


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