The Spanish electrical system wastes an important – and growing – part of its potential for electricity from renewable sources. It is a fact that worries experts. The system dispenses with windmills or solar plants, or orders their operation to stop because there is not enough demand to absorb that supply.
Given the current low demand for electricity – we are consuming less than in 2003 – the occasional abundance of renewable resources (wind and solar) causes, especially in spring and autumn, collateral effects, which pose new challenges.
The lack of storage systems to store clean electricity and be able to sell it at the right times (batteries, pumps) or the lack of electrical interconnections powerful enough to bring energy to our neighbors to the north are some of the causes that explain this wastage. .
The economy is not decarbonized and is not electrified at the required rate, something essential to reduce emissions and mitigate global warming. It does not occur either in the transport system or in heating.
The impossibility of taking advantage of the full potential of renewable electricity sources is a metaphor for how the decarbonization of the economy (electrification) is not advancing at the desirable pace. Many experts see a lack of synchronization between electricity supply and demand, on the one hand, and the insufficient deployment of electrical connections, on the other.
The waste of this potential (wind turbines and solar plants) occurs because there is not enough electricity demand or because it is lower than initially estimated.
It can occur for structural reasons, when there is an "excess" of renewable generation and having to maintain a minimum of technologies in operation (generally nuclear and combined cycles), or for circumstantial reasons, such as a more or less punctual simultaneous abundance in a node of wind and/or solar resources, or when demand drops more than expected, especially on holidays that already have little demand in themselves.
The interruptions of renewable sources –due to “technical restrictions”– led to a total of 78 GWh (78,000 MWh) not being introduced into the transmission grid between January and February 2023 (winter months with a lot of wind generation). of electricity production (of which 72 GWh corresponded to wind power), 4 GWh to solar thermal and 2 GWh to photovoltaic. The equivalent of annual consumption was lost in those two months! of about 22,000 families; that is, more than 60,000 inhabitants, more than the annual electricity consumption of a provincial capital like Segovia, according to the Wind Energy Business Association (AEE). Unused electricity from renewable sources has multiplied by six in one year (since in 2022 the disconnection only affected 13 GWh).
This situation occurs in different phases. If the electricity system operator (OMIE: Operator of the Iberian Energy Market), which is in charge of matching supply and demand, finds that there is not sufficient demand for the generation offered, it cannot be matched or scheduled the next day or in the following hours.
Red Eléctrica, for its part, can also intervene in the last hour before the delivery of energy, in a last attempt to match supply and demand in the so-called adjustment markets. During the last year (rolling) the reduction in renewable production (or net discharge) in these adjustment markets (last minute) has been 0.8% of total production, says the company.
But there is more. Along with the losses in the generation and demand balance, there are interruptions and forced stoppages in the production of clean electricity in areas of the network that present "saturations as a result of a high concentration of renewable production at certain points and at certain times". , says Red Eléctrica.
These interruptions, attributable to “system security” reasons, are another cause that prevents everything that the renewable resource would allow from taking place.
Red Eléctrica maintains that this “zero discharge” (technical restrictions) is far from the admissible limit. It alleges that it represents 1.6% of the total, "well below the 5% that European regulations consider acceptable" for a level of penetration of renewables of 50% for the annual calculation (Spain reaches 52% so far year), and is below the values known from other countries. Renewable energy that is not placed on the daily market does not have financial compensation, but that which cannot enter due to the adjustment mechanism or suffers from technical restrictions that have arisen does receive compensation.
Salvador Salat, co-delegate of UnefCat (photovoltaic sector), stresses that this wastage of renewable resources has been growing and that "problems have multiplied this past spring" coinciding with an increase in this clean production.
In his opinion, "if what happened this spring is extrapolated to the entire year, that 1.6% loss (brought up by Red Eléctrica) would surely be close to 5%," he says. “And taking into account that renewables represent 50%, what is really lost can be 10% of renewables. In other words, from a wind farm with 10 mills, one mill would be wasted; and from a 10-hectare photovoltaic plant with 10,000 panels, an entire hectare and 1,000 panels are useless”, says Salat.
"Furthermore, it is not possible to verify if it affects all generators in a homogeneous way, or if it affects some critically, and others, not at all," he laments.
"The figures clearly indicate that generation capacity has increased and, on the other hand, demand is falling," says Heikki Willstedt, director of energy policies and climate change at PREPA. The economy is hardly being electrified with technological changes, such as the introduction of electric vehicles or heat pumps, despite being much more efficient than alternatives that burn fossil fuels.
In fact, the demand for electricity has contracted in recent times due to the chain of mild winters and due to an economic recession in the industrial sector.
The desirable goal of decarbonization involves reducing energy demand, but this goal should lead to an increase in electricity generation. Because? An example: changing a combustion car for an electric one reduces the demand for energy by four, but as a counterpart, the demand for electricity increases.
What happens is the drama of an electricity market that without sufficient storage systems means that the offer must be exactly equal to the demand. It's a fry and serve market. If there is no demand, the offer must fall in the same proportion; if not, the power grid collapses; It is the dreaded blackout or widespread blackout.
“Reducing the demand for electricity is the opposite of what we should be doing, since to decarbonise the economy we need electrification in many sectors that are not yet electrified. We are not doing well”, says Assumpta Farran, General Director of Energy of the Generalitat. Last year the electricity demand in Spain fell by 2.4%. "The focus has been on supply but not demand, and a market with a lot of supply and little demand doesn't work," she adds. The energy planning of Catalonia foresees that by 2050 76% of the energy will be electric and that it will reach 34% in 2030 (while now it is only 24%, after 100 years of electrification).
“We have jumped into the pool to produce with renewables; and we have not jumped into the pool to electrify the economy”, sums up Salvador Salat. “Mobility needs to be electrified, to make it electric, and also in the heating sector, which means promoting heat pumps,” he adds. “It has been convincingly demonstrated that building 2,000 windmills has turned out to be faster than changing 20 million cars”, he adds.
Precisely 2,000 5 MW windmills produce the same electricity needed to move 20 million electric cars an average of 10,000 km per year. The decarbonization of the electricity sector has been achieved thanks to private capital investments; on the other hand, the decarbonization of the other sectors (vehicles, heating) depends on the pockets of millions of citizens with limited income.
And while the demand for electricity contracts, the supply of renewables grows. Photovoltaic production has entered into a whirlwind in the electrical system.
In spring and autumn, electricity from wind and photovoltaic sources contributes almost all of what Spain consumes. In spring, “at daylight hours, we almost don't need nuclear power anymore,” says Salat. It's the first time it's happened. And it will be a phenomenon that will grow. More than 8,400 photovoltaic MW have been installed in two years. 5 years ago, in Spain there were 5 GW of power installed; in 2022 there were already 19.5 GW (of which there are 3,500 MW for self-consumption; and of these, 500 MW in Catalonia
This omnipresence of renewables in the market means that the promoters themselves are harmed. There is such an abundance of supply that it works against the owners of facilities that operate without receiving premiums.
The great contribution of renewable energy in the network at central hours, accompanied by the null presence of gas (which, being the most expensive energy, is the one that therefore marks the price of compensation for all other sources) means that in certain time slots, it is the hydro that sets the price, thereby lowering the remuneration for wind and solar. “These very low or almost zero prices occurred once before, some day; now they pass practically every day”, says Salat. The remuneration obtained by renewable plants in the strips of maximum insolation can be 20 euros per MWh or even 0 euros per MWh, since the gas (which sets the price) does not enter when it is sunny but in the afternoon and night.
