The Weight of Storing Energy - Solar vs. Gasoline

"davesaddiction @ opposite-lock.com" (davesaddiction)
02/14/2014 at 12:16 • Filed to: None

Posted in response to someone advocating solar energy as a replacement for hydrocarbons, in response to this post:

"Obviously, if you don't immediately use the energy you generate with your solar panels, you need to store the electricity. Let us now look at a few batteries and see how they compare on the energy density (energy per weight) with gasoline.

Type MJ/Kg Application

Li - Ion 0.6 iPhone

NiMH 0.4 Prius

Alkaline 0.6 Duracell Rabbit

NiCd 0.14 RC cars

Lead Acid 0.14 Cars' lights, engine start

Gasoline 45

As we can see in this table, battery technology is clearly far behind liquid fuels in terms of energy density and compactness : to store the same amount of energy as in gasoline, the batteries would weigh a little less than 100 times more. This is one side of solar energy and transportation that not everyone fully understands. The incredible energy density of liquid fuel and the amount of energy that is required to operate a car is often overlooked due to the low price and high availability of gasoline. Think about it: if we want to drive a typical electric car 20 miles, we will have to charge batteries with our 1 square meter panel for 50 days (or 50 square meters for 1 day). If we were to drive the gasoline version of this car, we would only need ~1 gallon of gasoline!

http://solarjourneyusa.com/solarvsgas.php

DISCUSSION (11)

Goshen, formerly Darkcode > davesaddiction @ opposite-lock.com
02/14/2014 at 12:18

Hey, natural gas is cheaper than petrol.

HammerheadFistpunch > davesaddiction @ opposite-lock.com
02/14/2014 at 12:21

I have no problem with the electric car. I switched from nitro to brushless in RC cars long ago because they were so much easier to work and and faster...but batteries blow the big one.

davesaddiction @ opposite-lock.com > Goshen, formerly Darkcode
02/14/2014 at 12:22

It's $0.48 per gal equiv. in Saskatoon!

Cynical > davesaddiction @ opposite-lock.com
02/14/2014 at 12:25

This is not very meaningful in terms of actually comparing the technologies. I love when keyboard scientists want to compare some inane numbers for no reason. Are you taking into account that only 30% of the energy density in gasoline actually gets converted to usable energy? Also, take into account that the batteries can generally be recharged, whereas with gasoline, it must be replaced each time. The gasoline requires huge amounts of transportation to transport those billions of gallons to each individual station as well. This is a very oversimplified comparison which is essentially meaningless. Petroleum is a scarce resource, whereas sunlight is not. The cost to make and maintain solar panels will come down as the technology is more widely used. I'm sure your type was saying the same thing when the first horseless carriages came around. "Horses just eat regular food and drink water! Petrol needs to be dug up out of the ground!" Progress requires work and energy. The money is still tied up in companies that have no interest in providing a cheaper fuel source while they are still making money hand over fist with old technology. The incentive isn't there for these energy companies, but it is also in all of our best interests to switch to something else.

PS9 > davesaddiction @ opposite-lock.com
02/14/2014 at 12:45

Kinja'd!!!

Hydrocarbons are better than any other storage medium in terms of compactness, distribution, production and safety. This is all moot though, because we have no reliable way to replace what we use. So will run out of them. "What will we use instead when this happens?" is not a question we have the luxury of ignoring, because it underpins both the current and continued development of global civilization.

One day, it will not be there for us to use anymore. That's not really a concern for us though, as nobody reading this will be alive on that day.

One day, it will be too expensive for everyone to use it as they do. That is of concern to everyone today, which is why the auto industry has experienced a sea change in terms of battery and electrics.

Every single automaker on this planet today who doesn't already sell some kind of battery-related energy recovery system in their product portfolio is either working on one, or partnering with someone who is. All three modern hypercars have battery recovery systems. All of our F1 cars will have them too. It is the product of a continuous, ongoing, multi-decade engineering effort involving significant time/energy and oceans of money invested. It is a sea change. If you don't like battery powered or hybrid cars, you will have more reason to hate the industry than ever before in the coming years.

davesaddiction @ opposite-lock.com > Cynical
02/14/2014 at 12:53

I'm all for progress and clean energy, but it makes me a bit crazy when people say, "let's just use wind and solar for all our power needs!"

I just quickly found this comparison (from a solar energy advocate!) that shows it's not really as easy as many people might think.

As far as incentive - there is massive incentive for any company that likes to make money to come up with a cheap, abundant, clean energy source. It does require work and energy, but if there was something that could easily take the place of hydrocarbons, we'd all be using it already.

Who Killed the Electric Car? Economics. Technology continues to improve, and I wish Tesla all the best, but alternatives will only succeed when they are viable economically. We're getting there, slowly but surely.

davesaddiction @ opposite-lock.com > PS9
02/14/2014 at 12:59

I agree that we can't ignore the question, and as much as I love the internal combustion engine, I'm all for technological advancement, as long as enthusiasts still have options.

Related: "The remarkable thing about this achievement is that Mazda earned these averages without having a hybrid or electric vehicle in its fleet."

PS9 > davesaddiction @ opposite-lock.com
02/14/2014 at 13:02

Kinja'd!!!

i-ELOOP qualifies as an energy recovery system. And they are engaged in h ybrid research using a tiny rotary as a range extender.

!!! UNKNOWN CONTENT TYPE !!!

PS9 > PS9
02/14/2014 at 13:06

Kinja'd!!!

Hungry for .svgs today, Kinja?

Cynical > davesaddiction @ opposite-lock.com
02/14/2014 at 14:17

"Economics" is a shell game. I'm interested in real, actual innovation, not the same old stuff over and over.

davesaddiction @ opposite-lock.com > Cynical
02/16/2014 at 20:45

Kinja'd!!!

Just sayin'...

http://en.wikipedia.org/wiki/History_o…