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What if there's actually a glut of energy?

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#1 joiner


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Posted 09 March 2011 - 11:08 AM

After playing around with...


Edited by joiner, 19 September 2012 - 05:29 PM.

#2 admin


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Posted 09 March 2011 - 06:29 PM

Er, I think you're going to have to explain this one a bit more :huh:

Seems to show that we're in excess supply of energy now?

#3 joiner


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Posted 10 March 2011 - 09:17 AM

:D We are, it's why it's still relatively cheap according to some, hence our profligate use of energy without thought for the consequences! And bear in mind that some people maintain we've reached the point of "peak oil" now, so it's downhill from now on.

The calculator gives you the opportunity to play around with future scenarios, although it will always be a simplistic "tool" because future energy supplies will depend on future energy policies, so no one can accurately predict the mix of coal/gas/nuclear/renewables. The calculator can only use best-guess ratios/percentages for each step you choose in each section, and the steps can be quite large (space being limited), so there will inevitably be an element of 'smoothing' in the consequent graphs.

It is just a game, remember. But a sombre one. Hopefully it will encourage some thought on current energy use and future energy policies. :rolleyes: Said more in hope than expectation. :(

Edited by joiner, 10 March 2011 - 09:17 AM.

#4 joiner


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Posted 09 September 2012 - 09:32 AM

Nice to see this one still here.

And don't forget this seminal work of common sense, available here as a free download...


That url also directs to the errata that makes sense of some of the original typos...


Edited by joiner, 09 September 2012 - 09:33 AM.

#5 temp


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Posted 09 September 2012 - 09:57 AM


Posted 09 March 2011 - 12:08 PM
Interesting question asked on the GBF after playing around with...


I don't understand that chart for "UK energy supply". If you turn up the amount of nuclear power then the total goes up as expected. However if you leave nuclear alone and turn up the amount of on shore wind capacity then the total actually goes down. How does increasing the amount of energy from onshore wind (leaving others the same) reduce the total available?

Edited by temp, 09 September 2012 - 09:57 AM.

#6 caliwag


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Posted 09 September 2012 - 10:02 AM

I may be a bit simple, but I resent paying more for flour for my bread because the staple is hi-jacked to make biofuel for cheap yankie gas guzzlers, especially during the drought!

All this tosh about GM to feed the world when in reality we are fuelling others' profligate lifestyles.

#7 joiner


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Posted 09 September 2012 - 10:59 AM

Ha ha. Not necessarily yank gas guzzlers, Jim. A guy I've met off another forum drives a vast Dodge 4x4 which I had a go at him about "profligate" conspicuous consumerism. I was somewhat taken aback to be told by his tiny wife that they actually managed 47mpg, which went down to 32mpg when towing a fully laden ten-foot trailer, so more or less the same as my 1.9 Citroen Berlingo van!

And the debate about biomass feedstock continues to rage. Leaving wood burning out of the argument for the minute, the targetting of suitable crops "grown on marginal land", like palm oil or miscanthus grass...


...now appears increasingly disingenuous given the known consequence that the temptation to grow crops that attract the premium price ALL fuel attracts is too great to avoid a crafty redefinition of "marginal" to absorb marginally-productive land that is currently used to grow food crops.

I've seen arguments that insist crops like palm oil (particularly palm oil, in fact) have a potential for biomass feedstock once the main crop has been harvested, leaving the residue to be processed for fuel, which ignores its local use as animal feed and bedding. It's why the huge biomass-fuelled generating plant at Bristol was initially refused planning permission - its impact on overseas environments - a decision subsequently overturned by Whitehall.


It is particularly interesting to note the totally meaningless "environmental protections" included in the decision, which state (my italics to emphasise the use of catchphrase terminology to show how much someone cares):

"The Government is well aware of the concerns which exist about the potential
environmental impacts of widespread use of unsustainable biomass. It
therefore wishes to ensure that only sustainable biomass is used in renewable
energy generation.
It has therefore introduced sustainability criteria for solid
biomass and biogas under the Renewables Obligation (RO), and these are
applied to imported as well as to domestic biomass. The criteria include a
minimum greenhouse gas emissions saving of 60% relative to fossil fuel
measured across a lifecycle that includes cultivation, processing and transport,
together with restrictions on using biomass sourced from land important on
carbon or biodiversity grounds. Generators of above 50kW capacity must
provide to Ofgem a specified range of information on the biomass used
including its mass or volume, country of origin, biomass type and form.
Government intends that compliance with these criteria should become
mandatory for generators of 1MW capacity and above from April 2013 in order
to receive support under the Obligation4. The use of biomass from sustainable
sources is also a requirement of Planning Conditions (37) and (38), which also
ensure that where sustainability criteria apply to the feedstock to be burnt in the
generating station as a condition of eligibility for receiving financial assistance,
such as Renewables Obligation Certificates (ROCs), those criteria must be met
from the first date on which the Development is subject to those criteria."

It all means absolutely nothing in the real world of opportunistic commerce that is the fuel industry.

What REALLY amazes me is that all the talk about sustainable biomass feedstocks assumes that we're the only country going down this route. It's a bit like trying to get across to someone arguing the case for local biomass in the form of wood-burning technology, whether for heat or/and electricity generation using "local" "waste" timber, that the argument only holds for as long as the number of people doing it is restricted to numbers that are sustainable, in the sense of the fuel supply being sustainable year-on-year, assuming a regenerative cycle of planting and harvesting to meet a sustainable demand, and then assuming sufficient land is available that isn't needed to grow food in the first instance. And that's just "waste" timber. The sums get even more eye-watering when you start talking about cutting and planting vast swathes of woodland to feed the wood-chip burners that are pumping out vast quantities of particulate emissions that make talk of saving the environment a complete joke. Except that no one should be laughing!

Now expand that out to a global perspective.

#8 SteamyTea


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Posted 11 September 2012 - 09:01 PM

Most biofuel is ethanol from sugar cane I think I read somewhere, we hear little about that these days.

#9 SteamyTea


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Posted 19 September 2012 - 10:50 AM

I think that having in effect an unlimited supply of energy is not really a problem though there is some talk that it would raise overall global temperatures. But as a thought experiment, let us assume that 'unlimited' is twice the average Americans energy use for every person on the planets. So about 21 kW (184 MWh.year^-1). That should ensure a pretty good lifestyle for everyone.
Assuming that the population grows to 15 billion people in the next 100 years, that will be 3.15 x to^11 kW (2.8 x 10^12 MWh.year^-1).
Assuming that energy generation will take place by renewable means and is only land based, that only really leaves us with PV, but it could be in the most productive 'belt' around the Earth (this is a line that passes through Toronto and Marseilles (43.5° North). Luckily for us this has a good proportion of land area, almost 50% of the circumference at that latitude. So a good 10,000 km to play with and we can also go several km either side of this line. So how much land would we need to cover with today's PV technology.
A 1 kWp system at that latitude would produce in December about 60 kWh, so call that 720 kWh.year^-1, and cover about 10 m^2 for a tracking system (this is allowed as we have unlimited energy to play with, though in real life not rally practical or necessary).
Now the big sums.
2.8 x 10^15 (kWh.year^-1) / 720 kWh.year^-1
3.9 x 10^12 4 panel, 1 kWp systems
That would take up 3.9 x 10^13 m^2 of land area, or about 40 million square kilometres.
Now if that was places on the land in a 10,000 km long stretch it would have to be 4000 km wide, so would stretch, in European terms up to Oslo and down to Dakhla in the south.
Even if we doubled the efficiency of PV (or halved the energy use or kept the population the same) it is still an impractical scheme. Even taking the median production, instead of the worse case of December of 120 kWh per year per kWp installed would not make enough difference.
So what is the solution.
Instead of having double (or even equal to the average American, and I have nothing against them), how about if we had a quarter of their energy use, so around 3 kW (26.3 MWh.year^-2) or 50% more than we use today, the belt of PV would now only be 1000 km wide, so up to Paris and down to the Sicily. Still not really possible, so lets double the efficiency of PV and keep the population of the world at today's numbers. That would be a belt 250 km wide.
Not sure that that shows (except that I can make mistakes in arithmetic) or we need a very different World from today's.

#10 joiner


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Posted 19 September 2012 - 01:27 PM

Ah, let's dream.

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