Tuesday, May 2, 2017

Office of Energy Efficiency & Renewable Energy Electric Vehicle Community Readiness Resources

EERE EV Community Readiness Resources

U.S. Department of Energy, EV Everywhere Electric Vehicles: Stakeholder Solution Center

States and Municipalities

States and municipalities are key players in increasing EV readiness.  The best way for states and municipalities to improve their EV readiness is to partner with their local Clean Cities coalition, which can connect them to specific regional resources and other relevant stakeholders.   


Providing charging at the workplace can encourage employees to purchase EVs, be an attractive employee benefit, and maximize all-electric miles driven by EV owners. The EV Everywhere Workplace Charging Challenge is a DOE program to have more than 500 employers provide workplace charging to their employees by 2018. 


Like consumers, fleets can benefit from the low operating costs and other benefits associated with EVs.  Local Clean Cities coalitions can help fleets decide which technologies and models will be most appropriate to meet their needs.

  • Handbook for Fleet Managers: This handbook on the DOE’s Alternative Fuels Data Center provides fleet-specific information on the basics of EVs, including issues like maintenance and charging.

  • Plug-in Electric Light, Medium and Heavy-Duty Vehicle Search: This tool on DOE’s Alternative Fuels Data Center provides information on EVs that can be filtered by class/type and manufacturer.

  • AFLEET Tool: Argonne National Laboratory’s Alternative Fuel Life-Cycle Environmental and Economic Transportation Tool allows fleet managers to calculate the cost of ownership, petroleum use, greenhouse gas emissions, and air pollutant emissions of alternative fuel vehicles.

Electrical Contractors and Inspectors

The installation of residential, workplace and public charging is essential to establishing an EV market. 

  • Electric Vehicle Infrastructure Training Program: This program provides training and certification at community colleges and electrical training centers across the U.S. for people installing electric vehicle supply equipment for residential and commercial markets. 

  • EVSE Residential Charging Installation Video: A series of segments on the Clean Cities TV YouTube channel walk electricians through the basics of installing EVSE in homes, including an overview of the equipment, the relevant National Electrical Codes, inspection, and best practices.


Through our partnership with the Edison Electric Institute, DOE is developing a suite of tools for utilities to support the use of EVs.

  • The Utility Guide to Plug-in Electric Vehicle Readiness: A guide from the Edison Electric Institute, this document covers structuring your company to support EVs, adding EVs to utility fleets, enhancing the customer experience, working with state and local governments, and managing the electrical grid with EVs. 

  • Utilities Power Change – This case study showcases how New Jersey's Public Service Electric and Gas Company, and Southern Company’s unit Georgia Power are launching workplace charging programs for their commercial customers.

Additional Resources

U.S. Department of Energy Workplace Charging Challenge Progress Update 2016: A New Sustainable Commute

At A Glance: Electric-Drive Vehicles

Charging Plug-In Electric Vehicles in Public

Charging Plug-In Electric Vehicles at Home

Resources for Electrical Contractors and Inspectors

Developing Infrastructure to Charge Plug-In Electric Vehicles

Plug-In Electric Vehicle Deployment Policy Tools: Zoning, Codes, and Parking Ordinances

Signage for Plug-In Electric Vehicle Charging Stations

Plug-In Electric Vehicle Handbook for Consumers

Workplace Charging: Charging Up University Campuses

Electric Vehicle Charging for Multi-Unit Dwellings (Webpage with links to resources and case studies)

Massachusetts Plug-in Electric Vehicle and Charging Infrastructure Case Study

Rolling Down the Arizona EV Highway (Case study)

San Diego Prepares for Electric Vehicles in Multi-Unit Dwelling Communities (Text version and video)

Houston Energizes Deployment of Plug-In Electric Vehicles (Case study)

Seattle Rideshare Fleet Adds EVs, Enjoys Success (Case study)

Alternative Fuels Data Center Publications (Search by keyword for additional resources)

Monday, May 1, 2017

Toyota Experimenting With Natural Gas Fuel Cells

Toyota is experimenting with using natural gas rather than hydrogen in a fuel cell vehicle.
The prototype hybrid system actually uses both fuel cells and a micro gas turbine to generate power. The turbine provides oxygen to the fuel cell in the form of compressed air. The oxygen reacts with the hydrogen and carbon monoxide to create electricity. Waste heat from the system is used to create additional power, and Toyota says the turbine is powered by leftovers from the process that splits natural gas into hydrogen and carbon monoxide.

Toyota claims the system is capable of generating 250 kilowatts of power, with 53 percent efficiency using only the fuel cell. Factoring in the use of waste heat to create power increases the system's overall efficiency to 65 percent, Toyota says, making it more efficient than a regular fuel cell. The fuel cell features a novel solid-oxide design that doesn't require a platinum catalyst, according to Toyota, and it operates at lower temperatures than conventional fuel cells.

How to compare the energy content of alternative fuels and gasoline or diesel

Question of the Month: How can I compare the energy content of alternative fuels and gasoline or diesel? What implications does this have for overall fuel and vehicle comparisons?

Alternative fuels have varying energy densities and are measured using a number of different units, which can make comparing them tricky. The gasoline gallon equivalent (GGE) unit allows drivers to make apples-to-apples comparisons of a given quantity of energy from alternative fuels and assess which fuel best suits their needs. Understanding the energy content of fuels can help inform comparisons of fuel prices and vehicle driving range.

What is a GGE? How about a DGE?
A GGE is a standardized unit used to compare the energy content of all fuels. This unit quantifies the amount of alternative fuel that has the equivalent energy content of one gallon of conventional gasoline. For medium- and heavy-duty vehicle fuel applications, diesel gallon equivalent (DGE) is often used.

How are GGE and DGE values determined?
Energy content is measured in British thermal units (Btus) per gallon of fuel, and is often referred to as the lower heating value of the fuel. To calculate GGE and DGE, the energy content of one gallon of gasoline or diesel is divided by the energy content of the comparison fuel. For example, conventional gasoline has an energy content of 116,090 Btus per gallon, while propane has an energy content of 84,250 Btus per gallon. As such, 1.38 gallons of propane has the same amount of energy as one gallon of conventional gasoline.

The table below displays the energy content, GGE, and DGE values of conventional and alternative fuels.

Energy Content*Quantity of Fuel in 1 GGEQuantity of Fuel in 1 DGE
Gasoline 116,090 Btu/gallon 1.00 gallon 1.11 gallon
Low Sulfur Diesel 128,488 Btu/gallon 0.90 gallon 1.00 gallon
Biodiesel (B20) 126,700 Btu/gallon 0.92 gallon 1.01 gallon
Biodiesel (B100) 119,550 Btu/gallon 0.97 gallon 1.07 gallon
Compressed Natural Gas (CNG) 923 Btu/cubic foot (ft3)
20,160 Btu/lb
125.77 ft3
5.76 lb
139.21 ft3
6.37 lb
Liquefied Natural Gas 21,240 Btu/lb 5.47 lb 6.05 lb
Ethanol (E100) 76,330 Btu/gallon 1.52 gallon 1.68 gallon
Ethanol (E85)** 88,258 Btu/gallon 1.32 gallon 1.46 gallon
Electricity*** 3,414 Btu/kilowatt hour (kWh) 34.00 kWh 37.64 kWh
Propane 84,250 Btu/gallon 1.38 gallon 1.53 gallon
Hydrogen 288.88 Btu/ft3
51,585 Btu/lb
401.86 ft3
2.25 lb
444.78 ft3
2.49 lb
*Lower heating value. Source for CNG and hydrogen (Btu/ft3): Transportation Energy Data Book, Edition 35. Source for remaining values: Alternative Fuels Data Center (AFDC) Fuel Properties.
** E85 that is sold in the United States today actually contains, on average, approximately 70% ethanol. Therefore, E85 energy content calculated as [(.70) x (E100 energy content)] + [(.30) x (gasoline energy content)]
*** Electric vehicles are more efficient (on a Btu basis) than combustion engines, which should be taken into account when calculating and comparing miles per GGE (see below).

The values in the table above can help standardize fuel amounts for comparisons. For example, if you have 10,000 ft3 of CNG, you can determine the equivalent number of GGEs by dividing by 125.77 ft3 to get 79.5 GGE. Similarly, to determine the number of DGEs, you would divide by 139.21 ft3 to get 71.83 DGE.

How are GGE and DGE used to compare fuel prices?
Fuel prices can be represented in dollars per GGE or DGE for consistency in pricing between fuels. For that reason, the Clean Cities Alternative Fuel Price Report shows prices on an energy-equivalent basis (Table 3 in recent reports). If values for price per GGE or DGE are not available, you can do the calculation on your own. For instance, if one gallon of E85 is $2.04, you would multiply by 1.32 (see table above) to find that this price equates to $2.69 per GGE after adjusting for energy content.

What are the factors that impact how far I can drive between fill ups?
The energy content of fuels is one factor that affects driving range. Filling up with a less energy-dense fuel often means that you will not be able to drive as far. However, tank size and vehicle efficiency also play a significant role.

Some alternative fuel vehicles (AFVs) have similar tank sizes to conventional vehicles, while others have larger fuel tanks to compensate for the difference in energy content. For example, vehicles that run on propane and biodiesel typically have similarly sized fuel tanks as their conventional fuel counterparts. As you can see in the table above, both of these fuels have lower energy densities than their conventional fuel counterparts, which subsequently can result in lower fuel economy and shorter range per tank. In the case of propane, bi-fuel vehicles are available that can operate on both conventional fuel and propane for extended driving range. In addition, propane and biodiesel offer many other benefits that can offset this difference.

CNG and hydrogen vehicles, on the other hand, often have larger tanks to offset the lower energy densities associated with these fuels. Fleets and drivers purchasing a CNG vehicle may have the option to install an additional CNG storage tank onboard the vehicle. Alternatively, bi-fuel CNG vehicles are also available to extend the range. As for hydrogen, these vehicles tend to have larger fuel tanks overall.

Tank size is not the only other factor that affects range; vehicle efficiency also plays a role. For instance, all-electric vehicles (EVs) are significantly more efficient than conventional gasoline vehicles. According to FuelEconomy.gov, EVs use anywhere from 59% to 62% of the electricity from the grid to power the vehicle, while conventional gasoline vehicles can only convert 17% to 21% of the energy from gasoline to power the vehicle. This is one reason why EVs have such significant fuel economy advantages over conventional vehicles, even when you are comparing the fuels on an energy-equivalent basis.

Clean Cities Technical Response Service Team