The reports of oil's EROEI have been greatly exaggerated.

[roflwaffle]

This came up in another thread, but I figured it deserved it's own. Anyhoo... The problem with most EROEI figures for oil and that they are extremely limited. For instance the really high ones are just for discovery, and most are for extraction, or discovery and extraction.

Like most people on this forum know, after it's extracted, it still needs to get transported to the refinery, refined, transported to the pump, pumped, and finally used, where it has a terrible efficiency of use, much less than other forms of energy like efficiency.

Here's a wiki entry on the subject. As you can see, the EROEI of something like gasoline before it's used is only about 4-5, and once it's used, that drops to about 1.3 to 1.6. The EROEI of certain parts of oil in it's supply chain may be high, but it's not like it magically jumps from the oil field into our gas tanks.

Along the same lines, that's why it's financially feasible to use grid-tied solar panels to power an EV, but not do the same with an oil well in your own backyard, assuming it's accessible to you The reason is that the EROEI of electricity from solar panels is higher than the EROEI of gasoline. Once we use those fuels , that gap widens because electricity has a higher efficiency of use than petrochemicals for most applications.

[AlanE]

Well, all those long extension cords trailing behind cars are going to be a nightmare to untangle when people are driving home from work in the evening.

[roflwaffle]

Almost as bad as the smog!

But yeah, no extension cords are one of the advantages of batteries.

[AlanE]

Originally Posted by roflwaffle

Almost as bad as the smog!

But yeah, no extension cords are one of the advantages of batteries.

Yet you conveniently omit any reference to the EROEI of the battery system which powers these solar powered cars. Now, considering that a battery doesn't actually create energy and is a technology which simply enables the time-shifting of solar produced energy, to measure the system you have to borrow EROEI from the solar panels, meaning that you're seriously diminishing the EROEI of solar in order to get the time-shifting capacity to use its power anytime and anywhere, something that you don't have to do with gasoline.

[Xringer]

"Once we use those fuels , that gap widens because electricity has a higher efficiency of use than petrochemicals for most applications. "


That's very true when I compare heating this house with oil (@ $4 per gallon),
with electrically heating, using ASHPs.

Costing us $100 per month, instead of $400+ a month..

I want to stop using oil completely. Even get rid of it as back-up heat, if possible.
Not because I'm a tree-hugger, but because of the rising cost of oil..

I think there are a lot of other better uses for oil, besides burning it to keep warm..

[Ryland]

Originally Posted by AlanE

Yet you conveniently omit any reference to the EROEI of the battery system which powers these solar powered cars.

That is why most people who have electric cars, like my self, measure their electricity use at the wall, just like part of the cost of heating your house with fuel oil or natural gas is the cost of running that huge fan that blows the air around the house and the computer in the furnace that is always on (20 watts on my furnace, summer and winter), but that electricity that is lost in the charger and batteries not being perfect is counted with electric cars and the charger interlock keeps me from driving off with my cord still plugged in to the car.

[roflwaffle]

Originally Posted by AlanE

Yet you conveniently omit any reference to the EROEI of the battery system which powers these solar powered cars. Now, considering that a battery doesn't actually create energy and is a technology which simply enables the time-shifting of solar produced energy, to measure the system you have to borrow EROEI from the solar panels, meaning that you're seriously diminishing the EROEI of solar in order to get the time-shifting capacity to use its power anytime and anywhere, something that you don't have to do with gasoline.

Most readers will just search for that information online (eg embodied energy lithium battery) and find it within a few minutes. Finding info on rechargeable lithium battery lifespan is also pretty simple. As long as the pack makes it the equivalent of ~200+ full cycles, an EV will still have a better EROEI than a conventional car. As you can see from the second link, batteries used in most electric cars can currently last thousands of cycles, so for all intents and purposes the embodied energy of a battery pack has a minimal influence on EROEI.