Search This Blog

Charging A Nissan Leaf from a Gasoline Generator / Reflecting on Efficiency

In the past, I leased a 2011 Nissan Leaf & then purchased a used 2015 Nissan Leaf & built a special plug adapter with resistors to satisfy the ground fault circuit in the Level 1 EVSE included with both & used our Honda EU2000i generator to charge the 2015 LEAF with 1.4kw of energy for 4 hours to give it about 20 miles of range.


I was thinking about this while researching EV's this morning, having long ago traded my 15 Leaf for a 10 Toyota Prius. Here I present the basic math & ideas. 

EU2000i Honda Gasoline Generator Level 1 charging a Nissan LEAF using supplied 1.4kw charging EVSE cable 

Running the generator at 1400 watts output using the eco throttle results in loading the 1600w CW output to 87.5% loading

Maximum runtime about 4 hours at this setting, such that 5.6kw of energy produced & entered the EV of which 90% or 5kwh available 

Given 4.2 miles per kilowatt hour that is ~21 miles of range per 1 gallon of gas or 21 MPG theoretical 

In practice, actual fuel consumed per mile of EV range charge provided can vary

Factors such as HVAC use to defrost windows in winter increase energy consumption

Storing the vehicle outside in the winter or summer, cold or heat, increases cabin energy consumption

Under ideal temperate conditions, neither too hot or too cold, battery kept between 30-80% charged for long life & eco-driving or mild hypermiling, range per unit of charging energy can be as high as 5.3 mi/kWh in areas with flatter topography or a lack of energy draining hills or mountains

Furthermore, charging efficiency can approach 95% at 71 deg F, ideal for the laminate passive heat sink cooled lithium manganese spinel battery type.

EU2000 Generator from Honda also requires a special plug adapter that place a 1/2-watt resistor between the ground & neutral & hot & ground. Search google for how to make an adapter like this. This satisfies the EVSE's ground fault detection method to enable the supplied EVSE to charge from the generator

If the ECO throttle setting operates most efficiently & EO gasoline used, low fuel consumption results, boosting fuel economy to as high as 42mpg-e for the system

21 MPG-e the lower bound estimate, well below the average fuel economy of a Toyota Corolla as an analog for comparison. The higher possible bound approaches the worst-case fuel economy of a standard Toyota Prius used with outdoor parking in cold winter weather conditions in a mountainy local. 

Small generators like this also require oil changes & spark plug changes much more often than a conventional car engine. Operating between 3000-5000 RPM while generating electrical output, their lifetime limited to around 3000 hours total or as much as 10,000 hours if meticulously maintained with more regular oil changes, use an iridium tipped spark plug & hose changes & spark arrestor changes, cleaning and other associated filter cleaning & maintenance.  

My EU2000i Operation 

I store mine full of E0 or ethanol free gasoline to which a fuel stabilizer has been added. By keeping it full of fuel, the air space in the gas tank minimized so as to reduce fouling of the gasoline by oxygen present in the airspace in the tank. I also run the generator every few months for 15 min to 1 hour to keep fresh gasoline moving through the carburetor. I call this storage mode, active standby! 

13oz of 10w-30 motor oil changed every 50 hours. Spark plug checked at the same time & replaced every 200 hours. I keep a log book & pen with the generator to log runtime in minutes, date & time, including loads attached & wattage of loads. I also clean the Engine Air filter with warm water & soap & dry it & then oil it with clean motor oil & wring it out to reduce the oil content, with each oil change. 

No comments:

Post a Comment