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On Biomass: The World's Biggest Provider Of Renewable Energy

This is all explained on the EIA and Eurostat website if you look through them. I'm too busy to go through it.

April 27, 2014    View Comment    

On Biomass: The World's Biggest Provider Of Renewable Energy

Durwood


I provide links at the bottom to all data sources used.

 

Robert

April 27, 2014    View Comment    

On Biomass: The World's Biggest Provider Of Renewable Energy

Thanks Joshua

I quoted power density of biofuels in the context of their physical limitations. Comparing their power densities with other energy sources is a separate issue to that discussed.

Power densities of various renewables have been discussed a few times by me on this site. I would also caution anyone against thinking putting solar panels on urban school roofs will get us very far. Dense cities place limits on rooftop solar as I discussed in the piece below:

http://theenergycollective.com/robertwilson190/257481/why-power-density-matters

 

April 26, 2014    View Comment    

On Biomass: The World's Biggest Provider Of Renewable Energy

Willem

Can you please make an effort to edit your comments. This stuff is very difficult to read.

And what is this?

"Normal 0 0 1 251 1432 11 2 1758 11.0 0 0 0"

These badly edited lengthy comments really take up far too much space in the discussion. Please tidy up your comments for the benefit of other readers.

April 24, 2014    View Comment    

On Biomass: The World's Biggest Provider Of Renewable Energy

Thanks.

The subsidies part is even more surprising. But I guess meeting renewables targets while placating the agricultural lobby is a smart move politically.

April 24, 2014    View Comment    

On Biomass: The World's Biggest Provider Of Renewable Energy

Kolby

I do not recognise the importance of "technology plateaus" because I have no idea what they are. How can a technology plateau result in innovation? Do you know the meaning of the word plateau?

And you really should provide an actual example to illustrate what the following sentence means once you get past the fancy language.

"In energy transitions there are always technological plateaus and then breakthroughs that enable greater efficiencies and in rare instances ecosystem services that become a part of the energy paradigm. "

Cellulosic ethanol also appears to run into the same problems as corn ethanol. Low power density is just as much of a problem. And just this week a major study in Nature Climate Change calls into question whether cellulosic ethanol can actually reduce greenhouse gas emissions.

April 23, 2014    View Comment    

On Biomass: The World's Biggest Provider Of Renewable Energy

Jarmo

The evidence that sugarcane actually reduces emissions is questionable. See for example this PNAS paper on the indirect emissions that result from deforestation.

This is the fundamental problem. All crop based biofuels require the use of agricultural land. So where does this land come from? Well, it requires us cut down some trees. Unless people can rigorously demonstrate that a particular biofuel does not have massive indirect emissions then it is unwise promoting it through government subsidies or fiats.

http://www.pnas.org/content/107/8/3388.full

April 23, 2014    View Comment    

On Biomass: The World's Biggest Provider Of Renewable Energy

Forestry byproducts, of course, are already used relatively extensively for bio-energy. If you are a timber manufacturer then you will always have some waste wood lying around that can just burn to get some energy in your factory. Waste however is not particularly scalable. And it is also desirable to cut down on waste in production. There is still reasonable room to move in most manufacturing to cut down on waste, so it is dififcult to see by-products going very far.

Sugarcane in Brazil offers much higher power density than corn ethanol for example. It's almost an order of magnitude greater. However less than 2 watts per square metre is still problematically low, and it is far from clear if the deforestation that results from sugarcane production does not offset the emissions saved.

April 23, 2014    View Comment    

On Fossil Fuels are for Making Stuff

Allwood and Cullen convincingly argued in their book that you really need to deliver the same materials services, but with less material if you want to reduce emissions in steel making (and aluminium). Energy efficiency options are somewhat limited because materials manufacturing is now ultra-efficient.

On CCS I am skeptical. Most of the emissions from materials manufacturing are in China, and the percentage that is in the developed world goes down year by year. The chances of China, India or any other modernising economy sticking carbon capture devices on blast furnaces is incredibly low. And we aren't even doing this in western countries now, so I cannot see China doing it tomorrow.

 

April 16, 2014    View Comment    

On Can Nuclear Power and Renewable Energy Learn to Get Along?

Alan

The underlying assumption of what you are arguing is that natural gas is preferable to nuclear. And that burning more natural gas is preferable if we can loosen up the system to make way for more renewables. Is this not the case?


The economic arguments of course always feel more than a little half-baked. Imagine if I dangled a renewable power plant in front of you, one that could deliver an identical service as a nuclear power plant, but with the same economics. You can't honestly tell me that you would be complaining about it being uneconomic.

April 15, 2014    View Comment    

On Can Nuclear Power and Renewable Energy Learn to Get Along?

A secondary issue, which would be interesting to explore at some point, is whether, say, 40% nuclear and 40% renewables works better than 80% renewables, if you get storage figured out. My suspicion is that the technical challenges around a mix are possibly lower than they are for 80% renewables. Curtailment of renewables is a major challenge. And the biggest problem of course is the long stretches where there is no wind.

I have never looked to see if there is tecnical literature addressing the point though.

April 15, 2014    View Comment    

On Can Nuclear Power and Renewable Energy Learn to Get Along?

A common myth is that nuclear power plants have two positions: on or off.This myth is one of the reasons many think renewables and nuclear are incompatible.

However France produces easily available output data for all of its nuclear power plants. Available at the link below.

http://clients.rte-france.com/lang/an/visiteurs/vie/prod/production_groupe.jsp


For example Cattentom 1 ran at around 300 MW throughout most of last Sunday and then in the space of a couple of hours ramped up to 1200 MW. If you believe what many people say then this is technically impossible, but the French do it.

Strangely the same myth is believed by many regarding coal plants. Odd given how some countries run their entire grid on coal.

April 15, 2014    View Comment