Skriti stroški obnovljivih virov energije (2)

Spet primer iz Velike Britanije, ki OVE vire bazira na vetru, ki je sicer precej bolj izdaten in stabilen vir energije od sonca (piha tudi (predvsem) ob oblačnem vremenu, ponoči in pozimi). Vendar pa veter, podobno kot sonce, prinaša velike skrite stroške. Ljudje preprosto ne razumejo, politiki pa zamolčijo, da večji kot je delež OVE v energetskem miksu, več nadomestnih virov rabimo za nadomestitev izpada energije, ko sonce ne sije in kot veter ne piha, in za izravnanvanje frekvence v omrežju. Za vsak megavat inštalirane moči vetra ali sonca potrebujemo še vsaj en megavat inštalirane moči v plinsko-parne elektrarne (ker so fleksibilne in poceni) ter dodatne zmogljivosti za kratkoročno izravnavanje omrežja. Več kot dodamo zmogljivosti sonca in vetra, več nestabilnosti dodamo omrežju in večji so stroški za njeno ublažitev – ker sistem nikoli ni bil zasnovan za obvladovanje prekinitev dotokov energije. Več kot vlagamo v sonce in veter, večji postaja problem za elektroenergetski sistem in večji račun za njegovo odpravo.

Zato, če smo pošteni, povečana vlaganja v zmogljivosti vetra in sonca zgolj preusmerjajo prepotrebne naložbe stran od zanesljivejših in stroškovno učinkovitejših virov energije. V majhnem obsegu so te investicije v zmogljivosti sonca in vetra koristno dopolnilo, da malce zmanjšamo izpuste CO2 poleti, v velike obsegu ali celo kot glavni vir pa so narodnogospodarsko škodljive (destabilizirajoče, drage in uničujoče za gospodinjstva in industrijo), da o njihovem negativnem vplivu na okolje in socialne razmere v nerazvitih državah (kjer pridobivajo potrebne kovine in minerale) ne govorimo.

Renewable energy was never going to provide cheap energy. People who think it does don’t understand how the grid works. The grid has one basic job – to keep the grid running within a frequency range. In grid terms, there is no such thing as a power station. Energy sources are known as Balancing Mechanisms – which is why power stations have BM codes. Demand for energy goes up and down and the grid calls on balancing mechanisms accordingly to keep the grid frequency stable. If they fail, you get rolling blackouts.

Conventional  power stations are known as dispatchable energy. You can call on them at any time. To get the most efficient performance it’s best to have them running at their optimal thermal output. Only that doesn’t happen because the grid is obliged to use wind energy when it’s available – so gas stations have to be dialled down. They are then sat there, with all the overheads of existing, but they can’t be decommissioned because we can have weeks at a time with little or no wind. Then there are times with below average wind when you’re  running gas stations, but below their optimal thermal output.

Those losses are directly a consequence of using intermittent energy – and to get a true cost of wind energy, those costs have to be added to the cost of wind. But the statistics never show this. Balancing cost figures do not include the capital cost – and cost of wear and tear of gas stations.

Moreover, the capital cost of windfarms cannot be directly compared with other sources of power. A gas station might cost around £800m, whereas a wind farm will cost less. But that wind farm will need replacing in under twenty years and will need nee pylon and substation infrastructure. It is not cheap to build and the industry believes more than £50bn will have to be added to bills to connect new wind farms to the grid. Onshore conventional power can use existing infrastructure.

Moreover, the cost of wind is not coming down as the industry claims. Renewable energy is no different to conventional energy in that it requires a great deal of rare earth minerals, the price of which is skyrocketing.  Only now, we have to ensure that for every GW of wind capacity we add, that there is equivalent backup capacity. That means either new gas plant (because it’s the only thing you can build quickly), or rely on interconnectors to import energy from Europe – just as Europe is shuttering its own nuclear plants and the French nuclear fleet reaches retirement age. We have not seen the last of energy shocks.

Consequently, wind is diverting much needed investment away from more reliable and cost effective sources of energy. The £50bn required for new substations and transmission lines form the north sea alone would pay for two respectably sized nuclear plants. The renewables “industry” has consistently lied about the costs and reliability of wind. The more wind capacity we add, the more instability we add to the grid, and the greater the costs of mitigating it – because the system was never designed to cope with intermittency. The more we invest in wind, the bigger the problem becomes, and the bigger the bill to correct it.

Vir: Pete North, Twitter

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