Energy Storage

Isentropic energy storage system with gravel heat pump
Li-air-charge-discharge (Na9234)
To match supply with demand, energy storage is needed
To form the crumpled graphene, a sheet of polymer material is stretched in both dimensions, then graphene paper is bonded to it. When the polymer is released in one direction, the graphene forms pleats, as shown in the bottom left image, taken with a scanning electron microscope (SEM). Then, when released in the other direction, it forms a chaotic crumpled pattern (top left). At top right, an SEM image shows the material in a partially crumpled state. At bottom right, SEM image of a piece that has been crumpled and then flattened out.
Central wave in Brazil
Toyota Central R&D Labs

Energy storage is an emerging technology that is revolutionizing the automotive and electrical utility industries in addition to other sectors. This page is dedicated to providing some basic information on energy storage technology.

News Links:



Renewable Energy World - Energy Storage

Science Daily - Batteries

Policies and Programs:

California Public Utilities Commission

Technology and Research Links:

Charging calculator - Tesla Motors

Organic flow battery, and here

Rocky Mountain Institute - Electricity - Energy Storage

Thin Red Line Aerospace - Undersea CAES bags

Waste Heat Generation - Cyclone Power Technology

Falco Fusion Sports Electric Wheel - eBike Technology

Aqueous Hybrid Ion (AHI™) battery technology

Some Typical Specific Energy Densities [kWh/kg]:

0.00001 Electrostatic capacitor (typical electronic applications)

0.005 Supercapacitor (typical electronic applications)

0.018 Aqueous Hybrid Ion (AHI™ Aquion M-line, 25.5 kWh)

0.019 Liquid-metal battery (Ambri 2014 Beta Core, 35 kWh)

0.03-0.05 Lead-acid battery

0.08 Nickel-metal hydride battery

0.19 Alkaline battery

0.1-0.24 Lithium-ion battery

0.15-0.5 Sodium-ion battery (Faradion)

0.83 Gunpowder

1.4 TNT

2.6 Lithium-sulfur battery (Hyundai R&D)

4.5 Wood

4.67 Protein

4.72 Carbohydrates

>5 GigaCapacitor (White Paper by D. Rivkin)

5.47 Methanol

6.7 Coal

10.3 Fat

11.6 Lithium-air (Li-O2) battery (Argonne National Lab)

11.9 Aviation fuel (Jet A), kerosene

12.8 Gasoline, Diesel, Fuel oil

12.9 LPG

14.9 Natural gas

34.2 Hydrogen (compressed at 70 MPa)

2.3 x 107 Uranium 235

2.5 x 1010 Mass-energy equivalence E = mc2

5.0 x 1010 Antimatter

Some Energy Storage Equipment Costs [$US/kWh]:

$50 predicted cost for stationary storage

Source: Eric Wesoff, May 24, 2012, GreenTechMedia

$82 Lead-acid battery

Source: $112/115 Ahr @12 V, Sears DieHard deep-cycle marine RV

$100-200 target cost for all-electric car

Source: Eric Wesoff, May 24, 2012, GreenTechMedia

$125 GigaCapacitor

Source: White Paper by D. Rivkin

$160 Zinc hybird cathode (Eos Aurora)

Source: Eos Energy Storage, website, January, 2015

$250 cost for 4 MWh stationary battery system

Source: Chet Lyons, April 1, 2014, GreenTechMedia based on AES Energy Storage battery systems

$400 present (approx) cost of Tesla Model S Lithium-ion battery

Source: Clay Dillow, March 19, 2014, CNBC

$500 target for Liquid Metal Battery


$587 Aqueous Hybrid Ion (AHI™ Aquion M-line, 28.6 kWh)

Source: Budget quotation from Aquion, January 15, 2015

$1600 Lithium-ion battery w/ integrated converters

Source: $64k/40kWh Coda Energy

$53,900 Supercapacitor

Source: $1,456/83F @48 V, Maxwell Technologies BMOD module

Some Energy Transportation Costs [$US/100-miles]:

$0.15 Electric bicycle

Source: ResearchGate: Using national average electrical energy cost of $0.12/kWh, 1.2 kWh required to go 100 miles at an average speed of 10 mi/hr, 83.3 mi/kWh, time to charge approximately 2 hr.

$5.31 Tesla Model S, 2014

Source: Charging calculator - Tesla Motors. Using national average electrical energy cost of $0.12/kWh (3-15-2014) and standard 110 V, 12 A, outlet, 150 miles, $7.96, 66.3 kWh, 2.26 mi/kWh, time to charge 00:46:03.

$17.68 Toyota Tacoma, 2008

Source: My truck - 4.0L V6, 85% octane gas using national average gas cost of $3.50/gal (3-15-2014) all time averages are 309.1 miles, 15.6 gal, 19.8 mi/gal, time to fuel 00:03:00.