Sustainable energy and the value of efficiency

19 January, 2022

The Earth is at a turning point. In the midst of a climate emergency, we are heading towards a new energy model that guarantees the sustainability of the planet. And in this context, many terms such as sustainable energy have appeared in recent years. But what does it really mean? What types of energy does it encompass?

Sustainable energy is defined as energy that can be used to meet the demands of today’s society without affecting the energy needs of future generations.

Two characteristics stand out in this type of energy. The first is that it is naturally replenished and its use does not deplete it, although its capacity may be minimally reduced. The second has to do with the pollution it generates, since we are talking about a negligible environmental impact.

Within sustainable energies, it is worth noting renewable energies. Both concepts are sometimes used interchangeably, but they are not synonymous. It is true that renewable are sustainable, but sustainability includes other alternative energies that are not always renewable.

The main renewable energies

Renewable energies are an essential pillar that will make it possible to guarantee a sustainable supply in the coming decades. They are obtained from inexhaustible natural sources and are a clean resource with no or very little polluting impact.

Renewable energies are an essential pillar that will make it possible to guarantee a sustainable supply in the coming decades

The potential of renewables is undeniable and in recent years great strides have been made – in addition to their technological development – to make better use of their full potential.

There are different types depending on the natural resources used to obtain these energies. These are some of them:

• • Solar energy: uses solar radiation by means of panels to produce both electricity (photovoltaic energy) and heat (thermal energy).
  • Wind energy: is obtained through windmills, which transform the kinetic energy in the air masses into electricity.
  • Hydroelectric power: is the power that uses water to produce electricity. It is produced both from waterfalls in rivers and from water stored in reservoirs, as well as from seawater as a result of the movement of waves and ocean currents.
  • Geothermal energy:is the energy that takes advantage of the Earth’s own heat under the surface. Its transformation is used to produce electrical and thermal energy.
  • Biomass: organic matter of plant and animal origin is used to generate heat and sometimes also electricity.
  • Biogas: this gas is generated from the biodegradation of organic matter in the absence of oxygen and can be used to generate electricity or power heating systems, among other applications. Its use is key to boosting circular economy. Biomethane is generated from biogas, which has applications in sectors such as mobility and it can also be injected into the gas grid
  • Green hydrogen: another essential renewable gas in the energy transition. It is fully sustainable when it is produced from water through a process that separates it from oxygen. Among the key uses of hydrogen is its role in sectors that are difficult to electrify, such as intensive industry or heavy transport.

Year after year, these energy sources cover an increasing percentage of demand. In the case of Spain it was 21.4% in 2020, an increase of more than 3 points versus 2019. As a result, it surpassed the 20% barrier, which was the target set by European regulations.

The importance of energy efficiency

All these advances in the generation of clean energy must also be in conjunction with improvements in the field of energy efficiency. In other words, to obtain the same goods or services, or in different industrial processes, using the least possible amount of energy. It would serve little purpose in this sustainable route to resort to cleaner alternatives if resources are wasted instead of optimised.