Selecting the right contractor is one of the most important decisions you will make before installing a solar or renewable energy system. Qualified, licensed contractors save you time and money. Your contractor will:
Solar Energy: The Go Solar California Database of Solar Installers, Contractors, and Retailers allows you to search contractors by ZIP code and to filter results by the average cost per watt to learn how much real customers have paid.
Solar Water Heating: Visit the CSI-Thermal Contractor Database to find contractors who have installed systems in your area.
Your contractor must have an active A, B, C-10 or C-46 license (C-4 or C-36 for solar water heating installations). Check the Contractors' State License Board (CSLB) website or call 1-800-321-2752. When you meet the contractor for the first time, ask to see his or her CSLB “pocket license” and a photo ID to confirm you are meeting with an authorized contractor.
Contractors should visit your home and review your past energy usage and future energy needs. The two most important figures you want to know are: 1. the amount of electricity the system will produce, and 2. the net cost of the system per watt. Together, this information will provide an accurate measure of the size of the system and total cost. Each contractor should suggest a similar-sized system for your home’s need. If the size differs greatly, you will want to ask why.
It pays to be thorough and organized. Take advantage of PG&E’s helpful Bid Comparison Worksheet to compare what each contractor is offering and choose from your three bids.
Solar Energy Systems: Bid Comparison Worksheet (PDF)
Solar Water Heating: Bid Comparison Worksheet (PDF)
Here is some additional advice to help select the winning bid:
Compare apples to apples. Contractors often use different or confusing terms. Ask for clarification to make sure you are comparing the same thing.
Dig in for the details. Each bid should be comprehensive. All anticipated work and associated costs should be written out in detail. If not, ask for a more detailed estimate.
Use the Goldilocks principle. Consider a low bid carefully, as it may be a red flag that the contractor is cutting corners. Similarly, a high bid can mean an unnecessarily oversized system. Average project costs can be found at GoSolarCalifornia.ca.gov to help you gauge what to expect.
Ask questions. Do not hesitate to ask contractors questions about their businesses, the system to be installed or any terms you may not understand. Request references from previous customers to ensure that they are satisfied and the systems installed are performing well.
Are you ready to sign the contract and get your clean energy system installed? Before signing, read the contract carefully, including all warranties and maintenance agreements. Make sure that you have received the final price quote in writing, and only sign the contract after fully understanding the terms and total costs involved.
Under California state law, you should never pay a down payment of more than 10 percent of the contract price or $1,000 (whichever is less). Do not make the final payment until the system is fully installed and operating properly.