Historical milestone in the Portuguese electricity sector

According to data from REN (the Portuguese TSO), the renewable electricity produced in March (4,812 GWh) exceeded the consumption of Mainland Portugal (4,647 GWh).

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[eltdf_dropcaps type=”normal” color=”” background_color=””]T[/eltdf_dropcaps]he renewable electricity production accounted for 103.6 per cent of the electricity consumption, a value unmatched in the last 40 years. However, there were some hours when thermal fossil power plants and/or imports were required to complement the electricity supply of Portugal, these periods were nevertheless fully compensated by others of greater renewable production.

In the period under analysis, the daily share of renewable electricity in the consumption had a minimum of 86 per cent, on March 7, and a maximum of 143 per cent, on March 11. It should also be highlighted a 70-hour period, beginning on day 9, when the consumption was fully assured by renewable sources and another period of 69 hours, beginning at day 12.

These data, besides indicating a historical milestone in the Portuguese electricity sector, demonstrate the technical viability, security and reliability of the operation of the Electrical System, with a large share of renewable electricity. The previous maximum occurred in February of 2014 with 99.2 per cent.

In terms of resources, the main highlight goes to hydro and wind that accounted, respectively, for 55 per cent and 42 per cent of the monthly consumption. The total March production of renewables also avoided the emission of 1.8 million tons of CO 2 , which translated in savings of 21 million euros in the acquisition of emission allowances. In this analysis it is also worth noting the high monthly export balance of 19 per cent of the electricity consumption of Mainland Portugal (878 GWh).

This renewable share had a positive influence on lowering of the average daily wholesale market price, which was 39.75 €/MWh, price much lower than the same period of last year (43.94 €/MWh) when the weight of renewables in the electricity consumption was only 62 per cent.

Last month’s achievement is an example of what will happen more frequently in a near future. In fact, it is expected that by 2040 the production of renewable electricity will be able to guarantee, in a cost-effective way, the total annual electricity consumption of Mainland Portugal. However, it will eventually be necessary, here and then, the use of natural gas power plants, aggregated to interconnections and storage.

It’s not the first time Portugal can brag about its renewable achievements. In 2016, Portugal ran on 100 percent renewable energy for 107 hours straight — for more than four days, the country was powered by solar, wind, and water (with minor contributions from bioenergy, geothermal, and wave power).

Combining wind and hydropower

Portugal also uses an interesting solution to address the matter of energy storage. The country combines wind and hydropower by using night-time winds to pump water uphill. The water flows back through the generators when energy is needed — the so-called Pumped-storage hydroelectricity, which is also employed by stations in other countries.

Portugal also enjoys a useful distribution of renewable energy potential, with the most wind capacity being located in the north, and the most solar potential in the south. However, solar energy is lagging significantly behind wind and hydro energy, though several large-scale photovoltaic projects are currently underway.

APREN (Portuguese Renewable Energy Association) and ZERO (Sustainable Terrestrial System Association) considers it is vital that national public policies and the European framework called ‘Clean Energy for All Europeans’, which is currently in the final phase of decision, should enable Portugal to meet its carbon neutrality objectives by 2050, ensuring a strong expansion of solar energy and allowing decarbonization through the increase of electricity demand in the transport and in the heating and cooling sectors.