Green Collar Job Training - Free


Course Title
100 Home
101 Introduction
102 FAQ Page
103 Course Catalog
104 Green World
105 Demand & Supply
106 Conservation Careers
107 Solar Careers
108 Wind Turbine Careers
109 Entrepreneurs
110 Employee or Employer?
200 Demand Management
201 Summary
202 Residential Energy Profile
203 Ten Conservation Rules
204 HVAC System
205 Kitchen Appliances
206 Water Heater
207 Lighting
208 Laundry Appliances
209 Calculating Savings
300 Renewable Technology
301 Solar Energy
302 Solar Collectors
303 Solar Water Heating
304 Stirling Engines
305 Basic AC-DC Electronics
306 Silicon Solar Panels
307 Thin Film Solar Panels
308 Wind Turbines
309 Inverters
310 Grid Tied and Off Grid
311 Solar Site Survey
312 Solar Site Diagram
313 Sun Path Chart
314 Site Survey Worksheet
315 Wind Turbine Site Survey
316 Wind Turbine Worksheet
400 Solar Thermal Design
401 Solar Heat Overview
402 System Configuration
403 Site Survey
404 SRCC Compliance
405 System Specification
406 Bill of Materials
407 System Installation
408 Solar Heat Incentives
409 Document Package
410 Future Products
500 Solar PV Design
501 Solar PV Overview
502 System Configuration
503 Site Survey
504 Grid Tied & Off Grid
505 System Specification
506 Bill of Materials
507 System Installation
508 Solar PV Incentives
509 Document Package
510 Future Products
600 Wind Turbine Design
601 Wind Turbine Overview
602 System Configuration
603 Site Survey
604 Grid Tied and Off Grid
605 System Specification
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Green Collar Careers - Solar PV System Specification

Sizing the system is always a balance between what the customer can afford to spend vrs what they can afford.  In most cases the system is financed through a home equity loan with tax credits and any utility incentives to pay the loan down.  From the example given in Section 503 the homeowner borrowed $35,000 and will repay $30,540 from credits and incentives by the end of the first year, along with the accrued principal payments on their line of credit.

4000 watts DC is the most common size chosen for a residential solar PV system.  Most wholesalers price the 4000 watt DC systems the lowest because of that reason.  In some cases it will cost less to buy two 4000 watt systems then it will for a 6000 watt system.

From the site survey you should have identified the location and effective daylight the system will receive. 

You will need to sketch up and design the mounting rack system.  If you need some help learning about modular rack systems try this tutorial: T Slots Learning the System.  The rack mounting system will require a Bill of Materials.

Also during the site survey you will know if the system is Grid Tied or Off Grid.

For Grid Tied systems you'll need to contact the utility for a list of approved inverters, circuit breaker requirements, and surge protection requirements.

For Off Grid systems you'll need to identify all the powered equipment load requirements:

  • Continuous appliances such as refrigerators and well pumps
  • Lighting requirements
  • Comfort devices such as fans or any HVAC appliances
  • Entertainment
  • Cooking
  • Cleaning

From these devices you'll need to identify the expected demand and time of day usage.  What you'll find is that you'll never have enough battery power to run the expected loads at night, nor will you have the solar PV capability to produce enough power to keep the batteries charged.  Generally a 4000 watt DC system should provide 2 people with ample power as long as the power is not used for an HVAC system or to heat water.  Add roughly 1000 watts DC for every additional person.  Off Grid systems sometimes have to endure cloudy days suggesting more battery reserve would be recommended.  Each application will have a totally different set of requirements (and owners) so keep the #1 rule about Solar Energy in mind:

There is no perfect solution.