Energy Returned on Energy Invested Thread pt 2 (EROEI) (merg

[Bas]

When I was in thin-film r&d, no two panels had the same efficiency, and efficiency decreased rather quickly. Different locations on just one panel yielded diffrent out put and efficiency degredation. The thin film you install today probably won't be as efficient in just a few years from date of install. Unless there has been some eureka/miracle improvement in thin film panel manufacturing.

Jeff

since thinfilm seems to degrade so fast, what do you think about thin film vs PV panels or thermal solar and the prospect of each?

[slinky]

Prospects for each "can" and "should" be good. For now, a combination would be the most stable on an individual basis, but the initial capital investment? Oouuch. Not with out big subsidy. At least we know that given enough time and $, most tech based on sound proven science does improve. Becomes more powerful, more efficient. Cheaper.

All the above mentioned forms of solar, IMO have their pros & cons. Silicon PV Panels currently seem to be the most developed, thermal looks promising after I "wiki'ed" it. Storage is a big key issue, as it is for wind. Thermal seems to encompass that well.

I'm concerned about the time and money issue. It's unfortunate we didn't invest more in renewables sooner, when we had some breathing room. And can you imagine what progress we could make in r & d with what we're throwing at Iraq?

One can bet we're going to have to use combinations of everything in our bag of tricks to even reach a fraction of our current level of energy use. If we have an energy crash in the next ten or twenty years, and it happens that we have to go with what we've got before we raise the state of the art of renewables to furnish us with comparable levels of ff energy that we currently enjoy, developement could come to a grinding halt. We need more folks in lab coats NOW.

Jeff

[yesplease]

]You have built your argument on a ridiculous hypothetical.You said "if we have a cheap energy from another source . . . " Well we don't. Petroleum was that cheap energy that every other energy is dependent upon. Coal and uranium depends on trucks and railroads for transport. etc. No other fuel will propel this society. Maybe a different one. But not the one built and refined over the last 150 years.

Hardly. In terms of moving weight, an 80,000lb semi getting 5mpg is still eight times more efficient than a 5000 SUV getting 10mpg, and rail is similarly more efficient than transport by truck. We may not have enough to power every single oil waster (aka auto) in the states w/ biofuels, but we would have little trouble growing enough oil based fuel to power our semi/rail infrastructure. Especially after the extremely high oil prices needed to bring this about kill commerce as we see it now.

We have no need for more energy. We are already wasting it as fast as possible.

[slinky]

Ooops, wrote a response, got lost somehow...will repost later

[slinky]

First Solar? I worked there. Advice to you...buy into an igloo construction firm in Arizona...

[Gandalf_the_White]

Well I did have an excellent analysis typed up here for you and then my wife needed to do something on the computer and dumped it. Sometimes, but then how angry can you get before you have to look at all the stupid things you yourself have done.

So you get the really fast version.

Here is an equation for working with an entire portfolio of energy technologies

Let Gen[i](t) be the energy produced per unit time by one functional unit of technology i, Fixed[i] be the fixed costs of same, and Maint[i] be the maintenance costs, u[i] be the number of units in production. Let Q be a unit conversion constant (probably dollars per kW)


EROEI(t) ~ Q*Sum(u[i](t)*Gen[i](t))/Sum(u[i](t)*(Fixed[i]+Maint[i](t)))

You can examine this function in many ways and find that it does have the propeties we expect from an EROEI function. If any or all units in production were to become infinite the function goes to one, if all units went to zero the component functions would have to be picked so that the function went ot zero. You can only improve the EROEI by improving the power generated by any of the technologies, or reducing the costs associated with them. The energy needed to create and install the devices is added up in the denominator and the energy return in the numerator. If we have a constraint on funding say our total budget for adjusting the energy portfolio was $10B we could optimize the above function based upon the current distribution of units in production by adding an equation $10B = Sum(C[j](u[j])) and using the method of Lagrange multipliers. We could also make a prescription of how to get to a future desired portfolio using similar methods. if you think about this construction of the problem you see that it covers everything.

As for EROEI of solar in particular because solar is so small compared to other market shares getting 20% more efficient does little for us beyond increasing the lifetime value of the technology. There still exists the huge capital investment and time needed to make super-efficient solar competitive and influential. But yes I suppose there might be ways to eek out 3% more. Probably it will come with building with materials that are longer lasting and more abundant to help keep fixed and lifetime costs down in real terms.

I think our goose is cooked on the energy issue actually. But I do commend anyone for asking the right questions. The right answers to the wrong questions are no help at all.

[AirlinePilot]

Can someone point me to a source which can show the amount of energy required to refine one barrel of oil into gasoline? Or maybe a spread of different products?

I dont think Ive seen this and Im interested in comparing this with ethanol EROEI. Thanks.

[RdSnt]

http://www.eroei.com/

http://www.abelard.org/briefings/energy-economics.asp

[pup55]

Refinery Inputs and Outputs

This might be helpful. It looks as though it is pretty highly positive

[TheDude]

Burning Buried Sunshine: Human Consumption of Ancient Solar Energy

Also a short summary.

Since only about one-10,750th of the original carbon in ancient plant material actually ends up as oil, multiply 4.14 kilograms by 10,750 to get roughly 44,500 kilograms of carbon in ancient plant matter to make a gallon of gas.

Probably not what you're looking for but an interesting take on things. Also I've seen it used as evidence that FFs are an energy sink!

Found a nice piece at EB easy enough: Getting a decent return on your energy investment

In fact the EROEI for gasoline has already dropped precipitously, from the previously mentioned initial high of 100:1. It fell to 25:1 by 1970, and stands at about 10:1 today. This is because the size of the oil fields is shrinking, the depth at which oil is being found is growing deeper, and the quality of the oil that is being pumped is decreasing.

[pstarr]

I can debate the energy return of corn ethanol all day but I can not find definitive information on petroleum. You can try and look up Dr. Cutler Cleveland. This from Hubbert Speak

Ultimately at the energy break-even point, we can expect to retrieve no more than a single barrel of oil for every barrel of oil expended to find, drill, pump and refine that barrel of oil. At that point, we will have to turn to something else to meet our needs. According to his calculations, in the continental USA this could effectively happen during the first decade of the 21st century.

I have looked high and low for scientific studies but have found nothing. I've read 100:1 spindletop, 30:1 historical, and 10:1 now but I don't know where those numbers comes from.

[peak]

Suncor is proof oil sands EROEI is positive?

They say in a press release that they now produce 247,000 BPD of oil.

They might be mining from the most richest oil sands now, I don't know. The proof that EROEI is positive is because they run some of their machines using diesel (from oil) and they are profitable.

Just take a look at the balance sheet

http://finance.yahoo.com/q/bs?s=SU&annual

http://www.suncor.com/default.aspx?ID=53

in 2007, 215 million cubic feet per day of natural gas was produced – enough to offset energy consumption at Suncor's oil sands and refining operations, while still providing a surplus of sales to the North American market.

Nevermind

They are producing and using a lot of natural gas to process the oil sands?

I was going to say that EROEI was good until I see that they use natural gas. Anyone know why less than 215 million CU feet of NG is needed to produce 247,000 BPD of oil and refine it?

[FreakOil]

I've read that the EROEI on the Athabasca tar sands is 3:1, 5:1 or 7:1, depending on the source. They use natural gas to generate steam to heat up the tar. Earlier they planned to build a nuclear power plant, but that's been cancelled. It also takes two to four barrels of water to extract every barrel of oil.

I don't think the 247,000 bpd is for the whole sands. The total output was around 760,000 bpd in 2005. The U.S. Energy Department was pressuring the Canadians to raise output to 5 million bpd, but that may not be technically possibly, and it would be a terrible resource drain.

Here's some more material for you:

http://www.theoildrum.com/node/2915
http://canada.theoildrum.com/node/2931

[Tyler_JC]

Natural gas is far less expensive per BTU than oil. Thus, even if the energy return were less than 1, it would still be worth it.

No one in the real world gives a damn about energy, they care about profits. The process of turning crude oil into gasoline has a less than 1 EROEI but no one complains because gasoline is worth more than oil.

EROEI is a bogus figure but pretending that it matters for a second:

The energy return on energy invested of Suncor's process is very positive. It is at least 6:1.

The energy content of 115 million cubic feet of natural gas is only around 38,000 barrels of oil...

I'd say they're doing a pretty good job if they can take the equivalent of 38,000 barrels (including a large portion that they are selling) and turning it into 247,000 barrels.

[Starvid]

Hear hear.

[Tyler_JC]

Hear hear.

I just wish that people understood the purpose of EROEI calculations.

EROEI is an interesting side note but it has little basis in real life decisions.

EROEI is a component of cost curves but is not the only component.

When I drive an extra two minutes in order to save 10 cents per gallon on gasoline ($1.50 in total savings versus a few cents in cost), I'm making the "EROEI inefficient" decision but I'm making the economically smart decision. All rational people do the same.

[jato]

EROEI is an interesting side note but it has little basis in real life decisions.

You are correct. I would say EROEI does not matter to our economic system on the way up the fossil fuel curve. At some point, EROEI will matter on the way down the curve as oil EROEI approaches 1:1. After 1:1 oil will cease to be an energy source and it will be an energy sink just as hydrogen fuel is now. Yes the oil, like the hydrogen will still burn after it becomes a sink. We still use hydrogen fuel in the space program, but it will never fuel our economy.

I suspect once the tar sands become an energy sink, it would be more cost effective to use the natural gas from the oil sands process to directly power vehicles.

Currently oil via tar sands is energy positive. What about corn ethanol? It may be slightly positive, but the EROEI is certainly less than the tar sands.

What about shale oil? Is it energy positive? Or is it an energy sink?

When I drive an extra two minutes in order to save 10 cents per gallon on gasoline ($1.50 in total savings versus a few cents in cost), I'm making the "EROEI inefficient" decision but I'm making the economically smart decision. All rational people do the same.

I don’t see the above having anything to do with EROEI, you are inserting money into an EROEI calculation.

The only problem I see with EROEI is nobody can agree on a definition. What information goes into the calculation, etc.

[jato]

EROEI is a component of cost curves but is not the only component.

For those new to the concept (not you Tyler), never use money in an EROEI calculation:

Joules returned on Joules invested

Watts returned on Watts invested

BTUs retuned on BTUs invested.


Any organism will starve to death if it constantly expends more energy than it consumes.

A wolf that expends 100 calories to hunt and kill every 50 calorie rabbit will eventually starve to death, regardless if the wolf is aware of the EROEI concept or not.

[MD]

Hear hear.

I just wish that people understood the purpose of EROEI calculations.

EROEI is an interesting side note but it has little basis in real life decisions.

EROEI is a component of cost curves but is not the only component.

That has been the case, but won't remain so. As the mix changes away from sweet light as the primary source, so will the ERoEI balancing that occurs throughout the economy. Dismiss that fact and you will miss out on many opportunities. That's hardly a side note.

It's a cost curve component that is gaining significance, and will continue to do so. Those that fail to pay attention and give it due consideration risk making bad decisions.

[pstarr]

The only problem I see with EROEI is nobody can agree on a definition. What information goes into the calculation, etc.

Here is my attempt at a defintion:

"Eroei is a recurse industrial life-cycle analysis of the energy cost to produce and deliver a primary fuel to the consumer. It must include certain fractions of all components of the infrastructure that directly and indirectly support fuel acquisition and must be depreciated over the lifetime of the infrastructure.

I understand what I mean by 'recursive' because of my programming experience but I have trouble relating it to what others refer to as 'boundry'