Page 76 - The Engineering Guide to LEED-New Construction Sustainable Construction for Engineers

LEED Sustainable Sites 57

and the minimum number of preferred parking spaces designated for these shared
vehicles (LEFEVP4) by Eq. (2.4.10).

LEFEVP4 = FTE/267 (2.4.10)

The number of low-emitting and fuel-efficient shared vehicles and preferred parking
spaces (LEFEVP4) must always be a whole number, and any fractional results must be
rounded up to the next-higher whole number.
Options 1, 3, and 4 may be much more viable than it might seem from reading the
credit description, as the typical person may assume that the low-emitting and fuel-
efficient vehicles are mainly alternative-fuel vehicles, and prior to 2007 not many people
in the United States owned such vehicles. However, this category also includes many
gasoline-fueled vehicles. Nearly all hybrids fall into this category, but so do many of the
smaller, more fuel-efficient cars on the market. The current year’s listings and information
on how to purchase a book with ratings for prior years are available at www.greenercars.
com. For instance, in 2006 in addition to many hybrids, vehicles with ratings above 40 on
the ACEEE rating included the following models: Toyota Corolla, Hyundai Accent, Kia
Rio/Rio 5, Honda Civic, Pontiac Vibe, Chevrolet Cobalt, and Saturn Ion. Since many
people commute in the more energy-efficient vehicles, there might be a great demand for
preferred parking spaces, and more importantly, the 5 percent requirement for the
preferred parking spaces may be easy to fulfill without leaving parking spaces unoccupied.
Similarly, providing fleet vehicles with these vehicles may be more economical than
initially thought.
Option 2 LEED 2009 For LEED 2009 SS Credit 4.3 Option 2, the submittal should confirm
the number of total parking spaces provided. In addition, according to the version 2.2 and
LEED 2009 Reference Guides, there should also be a calculation determining that the
number of refueling dispensing locations is at least 3 percent of this number. However,
this may not be the proper calculation for all situations, and it may be more dependent on
the alternative fuels being dispensed. It is not the intent of the credit to have dozens of
refueling stations, but rather to provide alternative fuel for at least 3 percent of the vehicles
which could be parked. A dispensing location for some alternative fuels can service many
vehicles in a reasonable time and is usually regarded in the industry as the actual nozzle
or dispensing device. A standard dispensing machine may service more than one vehicle
simultaneously and may service many over a fairly short time, with some exceptions
where recharging takes a long time. To take these variations into account, the submittals
listed in the LEED-NC 2.2 and 2009 Reference Guides include a plan with the location(s)
of the alternative fueling stations, the fuel type being dispensed, the number of dispensing
locations, and the fueling capacity for each for an 8-h period. It is the opinion of the author
that the submittal should then also include verification that these fueling stations can
adequately service the requisite number of vehicles easily within a reasonable time frame
that is convenient for the vehicle users. Let AFV be this minimum number of alternative-
fuel vehicles which can be adequately serviced and, as previously defined, TP is the total
parking provided, then Option 2 will be obtained if Eq. (2.4.11) is valid.
AFV = 0.03 × TP (2.4.11)

The LEED-NC 2.2 and 2009 Reference Guides provide the following definition:
“Alternative Fuel Vehicles are vehicles that use low-polluting, non-gasoline fuels such