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Forums - General Discussion - On "ranking" users and people by preference

Qwark said:
Teeqoz

It really depends on what you mean by making a real difference. Will we achieve the 2 degree goal? Almost certainly not. But changes in the energy portfolio have made very noticeable contributions. If you look at my first chart, perhaps the most substantial trend is no the growth of renewables - but that phasing out of coal in favor of natural gas. Natural gas has about half the CO2 emissions per unit of energy compared to coal, and is also much better for air quality because it doesn't release dangerous areosols into the air.

Nuclear has gotten an unfairly bad rep, but I think changing that is a lost cause with regards to having nuclear replacing large amounts of coal towards 2050.

Also, if you look at the US, the trend points towards nuclear being pretty constant while fossil fuels declin (especially coal, as it's under attack from both natural gas and renewables). In Europe, there have been moderate declines in both nuclear and coal, but more than anything, renewbles have been the source for new, additional capacity, and hasn't really been replacing already existing capacity to a large degree.....yet.

https://www.eea.europa.eu/data-and-maps/indicators/overview-of-the-electricity-production-1/assessment

I think the outlook is very positive. While there will be some minor hiccups in the transition (like Trump wanting coal back in the US - not gonna happen BTW), the trend is unstoppable, and we'll get there eventually.

I forgot to mention, we might be able to remain within 2 degrees with carbon capture.

Replacing coal with gas is a win, because you also don't have to get rid of the poisonous ashes. What people often forget though is that gas is getting harder and harder to win. The same goes for oil. In the 60s the 'energy return of investment rate' (EROI)of oil was over 100. These days imported oil from the middle east has an EROI of 30 and domestic US oil is even lower than that. This graph shows the efficiency of using and winning fossil fuels in Canada.

Now imagine how low the EROI is in 2030, at that time 600 grams of carbon dioxide will be emitted by producing 1kWh electricity instead of 450. Still a bit better as coal these days, but the gap will become closer. The gap between renewables and fossil fuels will only widen. When it comes to grams carbon emitted per kWh. 

In this graph and my apologies it's in Dutch we can see the carbon emission in Germany sole caused by generating electricity. The red line displays the amount of renewable energy being produced. However due to Germany is policy to wanting to phase out nuclear faster than coal and the diminishing returns of fossil fuels. The actual carbon emission caused by generating electricity has only seen a slight decrease the last decade. Even though renewables really took off in Germany.

So what I mean by making a difference is the actual carbon emission caused by generating electricity or even better Energy as a whole to significantly decrease. In my country The Netherlands our grams carbon emissions per generated kWh is actually rising instead of decreasing. So that's why I think that even though renewable energy is on the rise it needs to rise faster if we want to decrease our carbon footprint.

 

So what is my primary concern is wether renewable sources can keep up and decreade carbon emission at the current rate if we include a slighty growing demand for energy, decreasing EROI and the increasing carbon emission per kWh fossil energy. Especially when countries like Germany are primarily targeting nuclear, because that's more popular for the public while burning brown coal and natural gas largely get a free pass.

Because there isn't an effective way to store renewable energy aside from electrohydroplants yet. And even when power to (hydrogen) gas becomes somewhat efficiënt it would have a negatively influence on efficiency. Yet lacking a method to converse or store renewable energy could destabilise the electrical grid.

In the Netherlands (3% actual renewable energy, burning imported biomass from Canada and incinerating waste don't count) on hot summer days with lots of wind, we actually stop wind turbines to prevent destabilisation of the national electricity grid. In Germany you could get a negative price also causing wind turbines to stop producing energy because it literally costs money. So all of the above combined is why I think Europe needs to put a lot more effort in the energy transition. Or as you said should rely way more on carbon storage, which is what the Netherlands are going to do. Prevent 2 or 3% carbon emission with renewable energy and more than 35% by storing Carbon under the Sea before 2030 to hit the European target. Although I doubt we are going to do that, since we also agreed to produce 14% of our energy sustainably in 2020.

I'd assume decreasing EROI for fossil fuels will accelerate the shift to renewables? Indirectly, EROI would also be a factor for price, as increasing energy demands to extract a resource should correlate with increasing costs of extraction as well.

Those are just my immediate musings, but this is actually the first time I've been introduced to the EROI metric. I'll have to look more into it.

As for storage, I think mechanical storage (pumped hydroelectric, flywheels and stuff like this) will provide most of the bulk storage capacity, while batteries will supply extra capacity that is necessary for very immediate changes in electricity demands.