Nekajkrat sem že napisal, da sta evropska cilja 100-odstotnega razogljičenja proizvodnje električne energije in hkrati 100-odstotne proizvodnje elektrike iz obnovljivih virov sonca, vetra in biomase med seboj konfliktna in neizvedljiva. (Zadnjič me je kolega Luka Snoj iz Inštituta Jožef Štefan sicer opomnil, da vseeno obstaja ena možna rešitev tega konflikta: ugasnimo vse jedrske, plinske in premogovne elektrarne in kurimo drva za ogrevanje in proizvodnjo elektrike (ker drva so biomasa in se torej štejejo med obnovljive vire) in bomo šli nazaj v kameno dobo. Zmanjšamo obseg razpoložljive energije in kurimo obnovljiv vir. No, jaz vseeno mislim, da bi s kurjenjem drv močno zasmradili hipernaogljičili ozračje in da je zgornji konflikt med obema ciljema nerešljiv).

Kolikor poznam, do sedaj še nikomur ni uspelo dokazati, da bi evropska energetska paradigma z obema konfliktnima ciljema lahko delovala v praksi. Torej da v Evropi naš energetski sistem v celoti preobrazimo v smeri 100-odstotne proizvodnje elektrike iz OVE virov sonca, vetra in biomase in da ob tem spravimo emisije CO2 na ničlo. Zappa, Junginger & Van Den Broek so leta 2019 objavili raziskavo v znanstveni reviji Applied energy, v kateri so poskušali ugotoviti, ali je to možno in koliko bi to stalo. Dve njihovi ključni ugotoviti sta: (1) tudi če bi lahko tehnično optimizirali tak idealen energetski sistem, bi bil tak sistem zelo drag (za 30 % dražji od sistema z nizkoogljičnimi viri, kot sta jedrska in vodna energija), in (2) 100-odstotno OVE energetski sistem ne bi zagotovil ravni zmanjšanja emisij, ki je potrebna za dosego evropskih podnebnih ciljev do leta 2050, saj bodo negativne emisije iz biomase z zajemanjem in shranjevanjem ogljika še vedno potrebne za izravnavo povečanja posrednih emisij.

Povzetek njihove raziskave:

In this study, we model seven scenarios for the European power system in 2050 based on 100% renewable energy sources, assuming different levels of future demand and technology availability, and compare them with a scenario which includes low-carbon non-renewable technologies. We find that a 100% renewable European power system could operate with the same level of system adequacy as today when relying on European resources alone, even in the most challenging weather year observed in the period from 1979 to 2015.

However, based on our scenario results, realising such a system by 2050 would require: (i) a 90% increase in generation capacity to at least 1.9 TW (compared with 1 TW installed today), (ii) reliable cross-border transmission capacity at least 140 GW higher than current levels (60 GW), (iii) the well-managed integration of heat pumps and electric vehicles into the power system to reduce demand peaks and biogas requirements, (iv) the implementation of energy efficiency measures to avoid even larger increases in required biomass demand, generation and transmission capacity, (v) wind deployment levels of 7.5 GW y⁻¹ (currently 10.6 GW y⁻¹) to be maintained, while solar photovoltaic deployment to increase to at least 15 GW y⁻¹ (currently 10.5 GW y⁻¹), (vi) large-scale mobilisation of Europe’s biomass resources, with power sector biomass consumption reaching at least 8.5 EJ in the most challenging year (compared with 1.9 EJ today), and (vii) increasing solid biomass and biogas capacity deployment to at least 4 GW y⁻¹ and 6 GW y⁻¹ respectively.

We find that even when wind and solar photovoltaic capacity is installed in optimum locations, the total cost of a 100% renewable power system (∼530 €bn y⁻¹) would be approximately 30% higher than a power system which includes other low-carbon technologies such as nuclear, or carbon capture and storage (∼410 €bn y⁻¹). Furthermore, a 100% renewable system may not deliver the level of emission reductions necessary to achieve Europe’s climate goals by 2050, as negative emissions from biomass with carbon capture and storage may still be required to offset an increase in indirect emissions, or to realise more ambitious decarbonisation pathways.

Vir: Zappa, W., Junginger, M., & Van Den Broek, M. (2019). Is a 100% renewable European power system feasible by 2050?. Applied energy, 233, 1027-1050.