Saturday, August 16, 2014

A real green guy

My friend Ophir is an engineer and his job is to manage projects for installing solar cells on large roofs of commercial properties for projects that are typically greater than one megawatt.  He has a real green job.   Ophir lives in Napa County and commutes to his office near my home in Marin County.  This is an 80 miles a day round trip.  Previously he drove his pickup truck when he commuted but on taking this job he bought a CNG powered Honda Civic and commutes using natural gas as his fuel.

His Civic get 40 MPG equivalent and he commutes 20,000 miles a year.  His old pickup got 20 MPG at best.   He would have used 1,000 gallons a year of gasoline had he not switched vehicles, now he uses approximately 62,000 standard cubic feet of natural gas a year.   Performing all the tedious algebra he would have emitted 25,000 pounds a year of CO2 in his truck and now emits only 9,500 pounds a year of CO2.  Of course he could have bought a gasoline powered Honda Civic and halved his CO2 foot print to 12,500 pounds a year.

Ophir also enjoys dollar savings by using CNG not gasoline.   His cost to fill up averages $2.40 a gallon equivalent.  He pays PG&E $2.20 per gallon equivalent at the PG&E yards where he can fill up during business hours and he pays Clean Energy $2.80 per gallon to fill up at their sites that are open for business far more frequently than the PG&E yard.  His bill for fuel in his car is now $1,200 a year versus $4,000 had he kept the pickup truck.  The fuel savings pay for his new car.

Ophir is a mechanical engineer and also a licensed contractor.  He is now investigating installing a natural gas compressor at his home.  PG&E has a special rate for homeowners who install home compression for fueling vehicles and the cost saving on his natural gas compared to buying the compressed gas at Clean Energy may well pay for his compressor as he will install the system himself.

His Honda Civic has a compressed gas tank that is set to operate at 3,500 psi.   Pretty high pressure!!   He told me he fills up once in a while in Berkeley California where the station actually compresses gas to over 3,900 psi.   Yeah those folks in Berzerkeley always had high blood pressure while protesting and causing mayhem.  The compression to 3,900 psi versus the rated 3,500 psi gives the car an extra 10% of range but I am not sure I would like to drive with an overfilled tank.  I am not sure I would feel too good with 3,500 psi behind my butt but the CO2 savings solar savings make Ophir feel comfortable.


  1. Natural gas as a transportation fuel is a no-brainer. Here you get a Btu per Btu reduction in oil imports. Other alternative transportation fuels may provide no relief. Ethanol from corn requires more energy to make the product than it contains. More oil may be required in the field to gas tank process for ethanol

    James Rust

  2. Dr Rust

    Of course using natural gas and LPG for transport makes sense and that is why the Department of Entropy will not promote it as Al Gore cannot make millions about lying. Sadly Dr. Moniz is as entropic as Dr Chu who was an out and out liar.