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We need your help. My friend Nick is working on a energy spreadsheet. In one of his earlier website post about ultracapacitors and EEstor a spreadsheet and model was included that contained a comparison of EEstor with Gasoline energy density. Unfortunately there was a serious error in the calculation. He created this model to help verfiy the numbers and approach. We would appreciate any feedback you have for Nick on this. From Nick G:
Energy Efficiency Tool (Excel)
Liquid fuels such as gasoline and diesel combined with internal combustion engines have excellent attributes which make them difficult to replace as stores and forms of creating mechanical work. Internal combustion engines with liquid fuels have the following competitive attributes:
- High energy density and work delivery
- Easy to transport
- Relatively stable and safe in “normal environmental conditions”
- Cheap to store
- Relatively efficient
- Slow to degrade over time
- Minimal maintenance (no physical fuel storage replacement required) like some batteries which only last a limited number of cycles
For Ultracapacitors to offer a challenge to liquid hydrocarbon fuels, they need to match or exceed these attributes. The tool attached is a way of comparing various energy storage technologies on a cost and weight basis
We are looking for reviews or enhancements to the spreadsheet model. Feel free to create graphs, expand the data set or correct errors or assumptions as well as expand the presentation.
Ultracapacitors offer the opportunity for enhancing other aspects of energy from intermittent renewable such as sun and wind, micro-grids, power smoothing or even the physical transport of energy. We are interested in learning more about the needs or design constraints of various applications. The idea is that knowing where the finish line is for various markets and opportunities helps educate people about the opportunities ultra-capacitors have for revolutionizing energy.
The use of ultracapacitors in various markets could significantly alter markets by changing the required nature of electric grids, economies of scale for home generation, transport and distribution of electricity. It is important to know where these inflection points are in terms of specific energy storage density, cost etc. Help us out. How far are we from the age of the electric jet? Where is the finish line for the future?
We will use the inputs and updates to the spreadsheet to publish a few more articles about ultracapacitors and their transformative potential.
Energy Efficiency Tool (Excel)
Readers have left 13 comments.
Does the model take into account that some technologies may not be fully charged or discharged in order to extend their life and other technologies may be able to use the entire capacity of the battery? This can significantly affect the actual capacity/range.
I suggest that if you are going to waste time trying to pair eestor with internal combustion, you might as well throw in pixie dust as well.
No.3 Cool Tool
I think it's a cool tool to see differences. I don't like to limit my thinking to a box like the commeneter before.
the tool does take into account the number of cycles that a fuel system is good for. you can even adjust for the distance required per cycle. So an 80 mile range used for 80k miles is 1,000 cycles. Lead acid would need a replacment before that for example. The idea is to compare fuel, storage and motive systems. People only care about getting there easily and cheaply. So we are working on pointing out what technologies compete or don't with fossil fuels from a cost and efficiency basis. It is a simple tool. maybe a chart showing the levels at one variable setting would be helpful.
I believe cell F23 has an incorrect formula and should be =F18+F20*(F21+1)
Also it would be helpful to add both city and highway driving MPG even though the EPA doesn't do it that way anymore. EVs are great for stop and go driving like you'd find in a taxi cab and without separate MPGs you can't show that. For the EV calcs you'd need to use the highway MPG.
"For Ultracapacitors to offer a challenge to liquid hydrocarbon fuels, they need to match or exceed these attributes."
apples and oranges in my view.
The ability to charge an EV daily nearly eliminates the need to hoard range with a tank of fuel. Also 20-30% efficiency in an ICE is considerably less efficient than 90+% for EVs. Also, it is intellectually dishonest to cite advantages of fossil fuels without mentioning the "elephant in the room" disadvantages.
A question -
Does it take into account the cold (or hot) weather factor? Electric vehicles come up short on cold and hot days because they have to power electric heaters/ coolers which will shorten range, gas engines (as a by-product) can supply heat and for very little mileage loss cooling. (Right now it is mighty cool around here)
The only other item (that I noticed) about the spreadsheet was that Boron can only burn in "pure" Oxygen. This means that additional energy will be needed for an Oxygen generator. The "air" comment should be "Oxygen".
Something else that would be useful is to give a percentage of the usable capacity for the battery options. For example GM recently said the Volt would only recharge to 80% of capacity and would only allow discharges down to 30% for the ICE kicked in. This is pretty typical of Li-Ion batteries but of course EEStor's EESU don't have this issue.
What about the effects of Regenerative Braking?