A couple of weeks ago, functionaries from the San Diego’s Metropolitan Transport System (MTS) proudly rolled out one of six new electric buses that they had bought.

These million dollar babies compete with their Compressed Natural Gas (CNG) siblings whose capital cost is nearly half that of the “Green New Deal” machines. The SDMTS spokesman said that they wanted to work the bugs out as they approach the state-mandated regulation that such public transportation be “all green” by 2030. The virtue-signaling peeps in the green-painted electric bus were touting the less noise and benefits to the environment of their vehicles, compared to those pesky CNG-powered coaches.

In my humble opinion, this move to what are known as EV (electric vehicle) buses is part of a conditioning program for passengers to get them used to higher fares, gradually escalated. Let’s face it: There is no rational cost basis for this decision otherwise. About 43% of electric power produced in California is from natural gas. The capital cost per kilowatt installed for a common combined cycle gas turbine generator power plant is about $1,000 according to the U.S. Energy Information Administration. In other words, a 150 megawatt CCGTG power plant should cost about $150 million. There are many factors to adjust the price that are site-dependent (e.g. location, ease of permits, etc.). A similarly sized Photovoltaic (Solar, or PV) power plant will cost 250% of the natural gas-fired CCGTG plant, or, $375 million. Of course, the sun doesn’t shine all day and we need power 24/7 so there are additional costs for storing power, and then discharging it to the grid when the sun isn’t shining. In other words, the PV power plant needs to be larger and batteries will need to be added to meet the 24/7 power demands in the new green economy foisted on Californians by ex-Governor Jerry Brown. I am uncertain what the multiple is, but I will hazard a guess that it will be close to double, or $750 million.

I am not a power utility expert, but can we assume, just for the sake of this example, that utility rates are a high multiple of the capital cost of the power plant, say 50%? This would mean that if your power was produced from natural gas and you were paying $0.25 per kilowatt-hour (kwh), that same delivered power to your home from a PV power plant should be $0.625 per kwh.

EV-powered vehicle proponents like to discuss mileage in terms of gallons of gasoline equivalent (GGE) or gallons of diesel equivalent (DGE). In my humble opinion, this is part of the scam they present to the public. After all, compare the mileage for the EV bus vs. the CNG-powered bus:

EV = 17.48 mpg DGE versus CNG = 4.51 mpg DGE

Wow, it looks like the EV bus is more efficient by a multiple of four. The problem is that the EV mileage is represented as a 100% efficient delivered unit of energy versus that inefficient bus with an internal combustion engine that runs on CNG (thermal efficiency is about 20%).

What do you think the average price per kwh is delivered to a San Diegan? It is about $0.25 per kwh. But how many miles does that EV bus go on a kwh you may ask? As noted above, the EV mileage is 17.48 mpg per DGE. There are 37.95 kwh in a DGE. That means the EV bus uses 2.17 kwh per mile. However, not all of the electric power stored in the battery that is charged from the grid and then discharged to move the bus and heat or cool passengers transfers 100% efficiently. Assume that it is 100% efficient for this discussion though. Therefore the cost per mile is about $0.55.

The price of CNG in November 2019 in Southern California is about $2.00 per gallon. The “energy,” a.k.a. heating value of a gallon of CNG is 92.5% of a gallon of diesel. In other words, since the CNG bus gets 4.51 miles per DGE, the bus would get 4.17 miles per gallon of CNG. That means the CNG-powered bus fuel cost would be $0.48 per mile. In other words, the “fuel cost” for the EV bus is 15% higher than that of the CNG bus.

The “fracking revolution” in the U.S. has made natural gas a readily available and inexpensive fuel. As the technology improves, the world will gain a huge windfall of additional natural gas reserves via methane hydrates. Expect natural gas pricing to remain stable is the message. The U.S. is a net exporter of natural gas via liquefied natural gas (LNG) tankers.

Fuel costs for EV versus CNG powered buses is 15% more in San Diego. The capital cost for EV- versus CNG-powered buses is nearly double. That leaves questions about maintenance costs and impacts to the environment.

The Tampa Bay Area's public transit system, the HART (www.goHART.org) published a study of CNG vs. EV bus comparisons a few years ago. They determined that miles between road calls were:

EV - 9,331 CNG – 45,557

Basically, HART determined that maintenance costs per mile were 12.5% higher for the EV-powered buses.

It was mentioned earlier that about 43% of California’s electric power is produced through natural gas-fired gas turbine generators. I have to plead ignorance on how much of San Diego Gas & Electric’s power is generated through natural gas combustion. However, the simple cycle gas turbine generator has a thermal efficiency of 30%. Once power is generated, transmitted, transformed into the local voltage required, versus the higher transmission line voltages, stored in batteries via charging station, then consumed to drive the EV bus, the equivalent amount of natural gas to produce the kwh needed at the bus level should be close to that consumed in the CNG-powered bus. The CNG internal combustion engine has a thermal efficiency of 20%. This means that virtually the same amount of CO 2 is emitted for an EV- versus a CNG-powered bus.

My colleague’s son has a Tesla and commutes 80 kilometers to work in Denmark. He has had his EV for five years. He needs to change the battery pack next year. A new battery pack will cost from one-third to half of the new car cost. EV bus manufacturers state that they can have a battery life of 15 years. This seems dubious today but technology continues to improve. However, components in discarded battery packs are very lethal to the environment and require special care.

Coming back to my original premise about the conditioning of people today for dramatic changes in the era of California’s Green New Deal, I reiterate the following:

EV buses cost nearly twice those of CNG; Fuel cost (mileage) for EV buses is 15% higher today than CNG. However, California will migrate to total green fuel by 2020 so expect the fuel cost to increase substantially, maybe as high as 250%; Maintenance costs for EV buses are 12.5% higher than for CNG; Battery change-outs will be costly and will make disposal of such environmentally abhorrent. If a bus is operated 1,000 miles per week and a bus’s lifetime is 1,000,000 miles, there will be at least one, and likely more, costly battery change-outs.

As a user of public transportation in San Diego, will the virtue-signaling bureaucrats who have tasted the anthropogenic global warming Kool-Aid convince you to pay the likely much higher fares to ride in a bus painted green?

Image credit: Tostie14/Kevin Tostado, via Wikimedia Commons // CC BY-SA 2.0