Page 349 - Fluid Power Engineering

Planning and Execution of W ind Projects 309

Access roads are permanent infrastructure that must be

between 16 and 20 ft wide, 150-ft inside turn radius with
load-carrying capacity of 250,000 lb or more, and single axle
load of 15 tons per axle for concrete trucks and 10 tons per
axle for transporters.
The turbine erection pads must be able to withstand loads

of 6000 pounds per square foot during lifting of nacelle,
rotor, and tower sections. In most large projects, a 500- to
600-ton crane is deployed.
Crane walk area is a temporary path adjacent to the access

road for the crane to move between two turbine locations.
This path must be 32–36 ft wide with minimal slope and
minimal dip/crest to ensure that a 300-ft crane with high
center of gravity can use to travel between sites.

Foundation Design
Foundation design is described in Chapter 9. This task is typically
performed by a foundation design consultant.
Electrical Design
Electrical design involves design of the collection systems, substation,
and interconnection to the grid. Design of collection systems require
soil thermal resistivity testing along the path of the buried cables. With
this information, the correct size cables are chosen. Other items in the
collection system are the protection system and grounding system.
The protection system is a collection of switchgear (fuses and circuit
breakers) that protect equipment from fault current (sharp rise in cur-
rent because of short circuit) by isolating the area with the fault. It
also allows isolation of parts of a circuit for the purpose of conducting
repair and maintenance. Utility will review and approve the protec-
tion system and substation design before allowing interconnection.
Substation design was described in Chapter 11.

Permits
The critical issues analysis step identified the list of permits required
and the agencies that issue them. In this task, activities related to
obtaining the permits are performed. In most locations, all levels of
the government get involved: Federal, state, and local. In an ideal
situation, a one-stop comprehensive permit issued by single agency
would eliminate the uncertainty around the permitting process. Some
stateshaveasingleagencythatmanagesmostofthepermitting,except
those that the federal agency has not delegated to the state agency.
Following is a list of the most common permits:

1. Transportation permit. Turbine parts, construction equipment,
and cranes are large and heavy, requiring transportation