2.3 kW Residential Project Hawaii

2.3 kW Residential Project Hawaii
10 Solar World Panels with 190 Microinverters

SolarWorld 230

SolarWorld 230
21st Century Crew completed a 6.9 kW residential project

Enphase M190 with Sharp 230

Enphase M190 with Sharp 230
Technician Wiring Inverters

Manoa 2.76 kW system

Manoa 2.76 kW system
2.76 array with Enphase m190

PV Wiring "PANELS-J-BOX"

PV Wiring "PANELS-J-BOX"
PV-Inverter

SOLAR HOT WATER SYSTEM

SOLAR HOT WATER SYSTEM
SYSTEM INSTALLED IN WAINAE

Tuesday, June 15, 2010

Strut Spacing and Pricing

Solar strut provides the foundation between the roof and solar array.  It is important to first draw and chalk out the layout then proceed to rafters.  Most homes are either built with a 16 ir 24 " distance between the two rafters.  Most spacing is done by using every other rafter or a 32 to 48 inch span.  This distance provides support for the array without comprimising and windload issues.  Solar strut is expensive and should be used prudently.  I learned this the hard way.  I was overy concerned with the wind loads so I spaced the strut every 24 inches and it cost an extra 1000 dollars.  I nearly lost my job, but rather took a pay cut. 

In the end, solar strut provides  a solid bond between the  roof with the array, but can put a damper on costs. 

Sunday, June 13, 2010

Hickam Airforce Base 147 kW Project

21st Century Technologies has begun a project on Hickam Airforce Base that is considered the largest armed forces installation in Hawaii.  After getting all of the roof materials to the project, we started the layout for 120 Evergreen panels that will be mounted to cool ply.  This new innovative roofing material has three mainfunctions.

1.  Provides strong material for historical roofs
2.  A cement called MBR is mixed attaches the cool ply to the roof.
3.  Two comprails are attached to the top part of the cool ply. 

The cool ply dimensions are 135.5 x 57.50 inches.  The panels are slightly longer than the width of the cool ply.  The layout must consider the difference between cool ply and panel.  We were able to fit 140 cool ply on the roof. 

Wednesday, June 2, 2010

Hidden Wires in Rafters, Beams, or Eaves!

There are times when an electrician will hide wires within the beams or rafters for a few reasons.  An open beam home will not have the options of hidding wires in the attic space, and consequently hide them inside the beams or on the side.  This can be a severe issue without the help of the homeowner, builder, or building plans.  It is imperitive to locate the wires in the beam before any penetration. 

A two man team with cellphones are crucial.  One man will find the wires, measure them from the eave to the wire and relay.  The roofer will mark the no zones on the roof and evaluate layout for pins.  Most likely the layout will be slightly different, but will not hinder structural untegrity.  A roof-bolt can not be more than four feet away.