AI-generated summary
The complexity of an energy system that integrates multiple energy forms contributes to future resilience and stability. Currently, the energy landscape includes renewables like solar and wind, alongside low-emission sources such as nuclear and waste recovery, replacing traditional fossil fuels. This diversified energy matrix is essential because electrical energy cannot be stored on a large scale cheaply, necessitating a mix of sources to meet demand reliably. Primary energy consists of natural sources in their original forms—such as hydroelectric, nuclear, solar, and wind—while secondary energy arises from converting primary energy, like using electricity to power a heat pump.
Transitioning to net-zero emissions favors the use of low-carbon technologies, especially at the local level, making fossil fuel use in homes increasingly obsolete due to health, environmental, and economic concerns. However, scaled applications like district heating or generating electricity from organic waste-derived natural gas can be less harmful. Polluting energy sources remain part of the transition to balance supply and demand fluctuations, as renewables like solar and wind are intermittent. Photovoltaic energy, being affordable and predictable, is central to this shift, but maintaining some polluting capacity temporarily ensures system reliability.
Bringing energy production closer to consumers through self-consumption and shared community solar initiatives enhances sustainability by reducing dependence on large utilities, cutting local pollution, and minimizing transmission losses. This proximity allows the energy to serve as a primary source for direct use or a secondary source when converted for heating or cooling, supporting the ongoing acceleration toward a clean energy future.
The complexity of an energy system based on multiple forms of energy can be a form of resilience and stability in the future. The current energy landscape combines renewable sources (solar, wind) with others that are not, but at least they do not emit GHGs (nuclear, waste recovery) as we remove fuel sources from the […]
The complexity of an energy system based on multiple forms of energy can be a form of resilience and stability in the future. The current energy landscape combines renewable sources (solar, wind) with others that are not, but at least they do not emit GHGs (nuclear, waste recovery) as we remove fuel sources from the diversified matrix.
But why do we need this energy matrix to be complex? Why not invest everything in a clean system such as photovoltaics? As Alejandro Micó advanced in his interview, “electrical energy cannot be stored”, at least not massively and at a low cost, so the rest of the energy sources are also needed in the short term.
What is primary electricity?
Primary energy refers to all natural energy sources in their original form before they are converted, and two main types can be distinguished: primary thermal energy and primary electrical energy. If this energy is transformed, converted or processed, it will be called secondary energy.
As the world energy expert Vaclav Smil points out, primary electricity refers to hydroelectric, nuclear fission, photovoltaic solar energy, hydroelectricity or wind power, to which must be added categories still in development such as tidal or wave energy added by the International Energy Agency.
Towards Net Zero, is it better to consume primary or secondary energy?
In your home, the primary energy could be using photovoltaic panels to illuminate or using solar thermal panels to have hot water. But that same electrical energy, used for a heat pump, would become secondary (from electrical to thermal energy). When the same electricity comes from the electricity mix, it is more complex because part of that electricity is already secondary.
Obviously, the most decarbonised technology will be preferable to the one that emits emissions, especially if they are local, so the burning of natural gas in a domestic boiler never appears to be something with much of a future. First, because it emits local particles against your health, second because it will worsen the climate crisis, and third because fossil fuels will rise in price.
But the same installation, scaled up and servicing dozens of buildings (district heating) or even used to generate electricity in a combined cycle plant, is relatively less harmful, especially if the natural gas is derived from organic waste that will stop emitting CH4 (with 56 times more global warming potential thanCO2).
Maintaining the ability to pollute to avoid disruptions
As Alejandro Micó usually points out in his Photovoltaic energy must be the basis of technological adoption, “because it is a reliable source, one of the most affordable and very predictable”. And, on the other hand, we know that when the Sun goes down there will be no generation. We can make up for part of the difference between demand and generation with wind power, but this is less predictable.
This is where polluting energies come into play, either because they discharge GHGs into the atmosphere or because they distill nuclear waste that then has to be managed. Maintaining the capacity to pollute, i.e. not dismantling polluting infrastructure for the time being, is another step in decarbonisation as we embrace photovoltaics and grow wind generators.
This transition to clean primary and secondary energies will be carried out as it has been done until now, although we are in the acceleration phase. The photovoltaic installation is so affordable that it is more worthwhile to open a photovoltaic system than any other collection system. In a few decades, faced with an almost fully electrified mix, the technology adoption curve will be delayed. In other words, every 10% of decarbonisation will cost much more than the previous 10%.
Steps towards a clean future, bringing the primary or secondary energy source closer to the home
At the beginning of this century (and this millennium) the possibility of self-consumption was opened, and now we also have facilities for shared self-consumption. The same community of neighbors can agree to cover its entire roof with photovoltaic panels, agreeing on a distribution system that is still static. It is expected that in the coming years it will be dynamic, so that if one neighbor does not consume, another can use his share.
Bringing production closer to demand is a prerequisite for sustainability. First, because it allows us to own our own energy, reducing family dependence on large energy companies; second, because there are clean solutions that do not pollute the local air, such as panels; and third, because energy transport losses are reduced.
In addition, this electrical fluid can be used as a primary source, either by running a computer or turning on the lights in the house; or secondary, making it easier to heat water in a thermos or using a heat pump to air condition the rooms.
