What are renewable energies and why are they important?

Most countries are deficient in  fossil fuels  — oil , coal, and natural gas—although the same could be said of the world as a whole since they  are by definition finite, non-renewable sources of energy.  They have been generated over millions of years in the subsoil from organic matter and their quantity is what it is, not one iota more, so their days are numbered.

“Fossil fuels comprise  80% of the  world’s primary energy demand and the energy system is the source of approximately two-thirds of global  CO2 (carbon dioxide) emissions.  If current trends continue or, put another way, Similarly, if the share of fossil fuels is maintained while energy demand  nearly doubles by 2050,  emissions will vastly exceed the amount of carbon we can emit when we need to limit the average global temperature rise to 2 degrees Celsius,” experts Scott Foster and David Elzinga in the article ‘The role of fossil fuels in a sustainable energy system’.

Roadmap: the Paris Agreement

There is a momentous date in this fight against greenhouse  gas  (GHG) emissions, the main cause of  global warming :  December 12, 2015. The Paris Agreement   came to the world  at the United Nations Conference on Climate Change, the current international protocol to stop the warming process. Its objective, beyond avoiding the increase of those  2 degrees Celsius,  is “to promote additional efforts that make it possible for global warming not to exceed  1.5 degrees Celsius ” with respect to pre-industrial levels.

That historical document did not mean the birth of renewable energies (they had been developing for decades in their modern technological version), but it did come of age as  the main solution to limit warming.  For two fundamental reasons: they come from essentially inexhaustible natural sources, such as the wind, the sun, the force of water or sustainably managed plant material, and since they do not emit GHG gases, they are the main tool for the energy transition towards  a world low carbon.  And to achieve it within the tight deadlines set.

Innovate by tradition

In reality, it is not a question of a technological innovation from scratch, but of taking up and evolving a tradition inherent to  human civilization.  The uses of renewable energy go back to the origins of sailing and continue in successive times such as river waterwheels that take advantage of the propulsion of a riverbed or a jump.

A crop of sunflowers is reminiscent of mobile plates that are oriented to the sun. And the traditional economy, from the dawn of the Neolithic to industrialization, is brimming with  examples of sustainable farms,  circular economy, recycling models, etc. For example, crop rotations, forest management thanks to the browsing of herds or energy-efficient adobe buildings that today could be described as bioclimatic architecture.

renewable mix

One of the most recognizable cases of this connection between past and future are medieval windmills and modern  wind turbine farms.  In fact, wind power is, together with solar, one of the renewables with the highest degree of maturity and projection. “Wind energy installed in the world  grew by 10% in 2019,  reaching 651 GW (gigawatts)”, according to data from the Global Wind Energy Council (GWEC). “China, the United States, Germany, India and Spain are the first world producers.

The world’s largest source of renewable electricity generation, in 2019 it reached an estimated 4,306 TWh [terawatt-hours]

Wind turbines generate electricity from the kinetic energy produced by air currents. The wind turns the blades and thus causes the rotation of a shaft connected to a kind of gearbox that increases the speed of rotation and provides energy to a generator. The latter  transforms rotational energy into electrical energy . Wind  farms  can be terrestrial, the most obvious, but also marine with minimal visual and acoustic impact as they are located far from the coast, from intense shipping routes and from areas of ecological interest.

For its part,  hydraulic energy  harnesses the force of river water so that hydroelectric power plants convert it first into mechanical energy and later into electrical energy.

According to the report ‘Hydropower Status Report 2020’, from the International Hydroelectricity Association, it is  “the world’s largest source  of renewable electricity generation, in 2019 it reached an estimated 4,306 TWh [terawatt-hours], establishing in this sense the greatest contribution of a renewable energy source”. Brazil and China are the two great world powers.

Water also supplies the energy of the seas to produce electricity using the movement of waves  (wave energy)  and tides  (tidal energy).

But the renewable source with the greatest growth projection is solar, specifically its  photovoltaic variety  (the other two systems are solar thermal and solar thermoelectric). In fact, it has exploded in the last decade and its rate of deployment will increase. The International Energy Agency (IEA)  forecasts that by 2040 it will have  multiplied by six  the power installed in 2018.

The natural diversity of the planet completes the album with consecrated and emerging renewable sources, from  biofuels  obtained from agricultural and animal remains to the production of heat and electricity through  biomass or subsoil geothermal  temperatures   , through the  recovery of waste that they cannot be recycled. All of them bring together a power called to increase their share in the global energy mix. According to the IEA, it would go from 13% in 2019 to 16% in 2030.

Social and environmental commitment

Before this century was inaugurated, renewables barely occupied an appendix in  Corporate Social Responsibility (CSR) policies . Today they are protagonists in terms of  sustainability , energy efficiency and respect for the environment in corporate reports. According to the Seventh Report on the Social Impact of Companies, by the SERES Foundation and the consulting firm Deloitte, ” 92%  contemplate the UN Sustainable Development Goals (SDGs) in their CSR strategy, which shows the importance of this trend to organize and articulate corporate CSR”. Specifically,  64%  of the companies  surveyed carry out specific actions linked to climate action, SDG number 13.

Large and small draw sustainable roadmaps that also involve their value chains and demand  good sustainable practices from their suppliers.  There is even a  specific intergovernmental body  in this regard, the International Renewable Energy Agency (IRENA), with  162 member countries.  It is not by chance that its headquarters are in the United Arab Emirates, one of the largest producers of crude oil.

Green future yes or yes

In the 1980s and 1990s, the initial development of  renewable energies  was generally limited to those countries whose energy bill depended on imported fossil fuels. They were conceived as a way to compensate  for imbalances in the energy balance.  But today they are consolidated as a vital necessity for sustainable development and the transition to a  new economic paradigm.

In most countries, two large sectors stand out in terms of energy consumption: transport and construction. In both, the contribution of hydrocarbons predominates, but  that reign is coming to an end  and 193 countries have committed to meeting the  United Nations Sustainable Development Goals (SDGs),  in particular number 7, related to energy. Another thing is that this substitution, the decarbonization of the economy and the renewable advance meet the necessary deadlines to face the climate emergency.

The progress is not homogeneous, it varies according to countries, and the European Union (EU) appears as the vanguard in the implementation of the SDGs to  cut that 30% of the CO2 emissions  generated by transport (almost three quarters correspond to the land movements), among other objectives. Some nations approve calendars for the progressive disappearance of combustion engines, so everything indicates that gasoline and diesel cars will have an expiration date and the future on wheels will be electric.

The same happens with the energy needs of homes and buildings, also linked to traditional fuels. Once again the situation is unequal, but the most environmentally aware countries, and with the most resources to take action, grant aid and subsidies for the energy rehabilitation of buildings and facilities, with an increasingly intense use of renewable electricity.

Almost Zero Consumption Buildings and home energy certifications with standards such as  Passivhaus , LEED or BREEAM contribute to cutting the 39%  of CO2 emissions attributed to the sector