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How Does Google Project Sunroof Work?
What Are the Best Solar Panels for Hot Climates? A Complete Homeowner’s Guide (2023)
By Dan Simms /
What is Google Project Sunroof and Is It Accurate? (2023 Guide)
Here are the key questions we’ll answer in this article:
- What is Google Project Sunroof?
- How Does Google Project Sunroof Work?
- Is Google Project Sunroof Accurate?
- Do We Recommend Using Google Project Sunroof?
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Each product and or company featured here has been independently selected by the writer. You can learn more about our review methodology here. If you make a purchase using the links included, we may earn commission.
What Is Google Project Sunroof?
Google’s Project Sunroof is a free online tool that helps homeowners calculate solar energy potential based on their roof structure and local weather patterns. It was created in 2015 by a group of Google Engineers led by Carl Elkin.
Project Sunroof can calculate the sun’s path to give an accurate account of your solar situation. It then uses industry-standard models to tell you the cost-benefit analysis of going solar so you can decide if it’s worth it. In 2017, the tool added a feature that also shows you nearby homes that have installed solar energy systems.
Currently, the Google Project Sunroof data explorer is only available in the U.S. and Germany.
SunPower
Best National Provider
Pros
- Most efficient panels on the market
- National coverage
- Cradle to Cradle sustainability certification
- Great warranty coverage
Cons
- Expensive
- Customer service varies by local dealer
SunPower designs and installs industry-leading residential solar and storage solutions across all 50 states. With a storied history of innovation dating back to 1985, no other company on this list can match SunPower’s experience and expertise.
SunPower earns its position as the top national installer on our list for a handful of reasons: It installs the most efficient solar technology on the residential market, offers the most expansive service area and backs its installations with a warranty well above the industry standard. All the while, SunPower pioneers sustainability efforts within the industry.
If that weren’t enough, SunPower systems come packaged with products all manufactured in-house by its sister company, Maxeon. This means that your panels, solar cells, inverters, battery and EV chargers are designed to work together and are all covered under the same warranty.
SunPower’s biggest downside? Its high-efficiency panels are considerably more expensive than most of its competitors’ products. However, its powerful panels are workhorses that make up for the initial cost with more backend production (think about this like spending more money for a car that gets more miles per gallon).
Facts and Figures: SunPower
| EcoWatch Rating |
|---|
| Better Business Bureau (BBB) Rating |
| Year Founded |
| Average Cost ($-$$$$$) |
| Solar Services |
| Brands of Solar Equipment Offered |
| Warranty Coverage |
| 5 |
| A+ |
| 1985 |
| $$$$ |
| Solar Panels, Solar Batteries, EV Chargers, System Monitoring |
| SunPower Panels |
| 25-year all-inclusive warranty |
Blue Raven Solar
Best Solar Financing
Pros
- Industry-leading in-house financing
- Competitive pricing
- Excellent reputation
Cons
- Doesn't offer solar batteries (coming 2022)
We like Blue Raven Solar because it understands that, for most homeowners, the cost of solar presents the biggest barrier to entry.
For that reason, Blue Raven Solar developed an innovative solar financing plan that offers in-house, flexible, zero-money-down options. The results speak for themselves, as Blue Raven Solar is now one of the fastest-growing solar companies in the nation and was recently acquired by SunPower. Its BluePower Plus+ plan (exclusive to Blue Raven) mimics the flexible structure of a lease while still providing the greatest benefits of owning your system.
Eligible homeowners enjoy 18 months of solar power before having to pay their first bill. When coupled with the federal solar investment tax credit (ITC), the initial energy savings can offset more than a third of the overall cost of a system before requiring a dollar down.
In contrast, other installers can only offer similar financing through solar leases, PPAs or third-party providers (such as Mosaic or Sunlight). Third-party loan providers can complicate the process, while opting for a loan or PPA will disqualify you from some of solar’s biggest benefits (additional property value, federal solar tax credit and local solar incentives).
Facts and Figures: Blue Raven Solar
| EcoWatch Rating |
|---|
| Better Business Bureau (BBB) Rating |
| Year Founded |
| Average Cost ($-$$$$$) |
| Solar Services |
| Brands of Solar Equipment Offered |
| Warranty Coverage |
| 4.5 |
| A+ |
| 2014 |
| $$ |
| Solar Panels, System Monitoring |
| Trina Solar, Canadian Solar, SolarEdge, Silfab, SunPower |
| 25-year manufacturer warranty; 10-year workmanship warranty, 2-year production guarantee |
ADT Solar
Best Warranty Coverage
Pros
- Industry-leading warranty coverage
- Expansive service area
Cons
- Some reported communication issues
- No leases or PPAs
ADT Solar sets the industry standard for warranty coverage by including a multifaceted guarantee, making it one of the top installers for homeowners who want added peace of mind.
Its warranty coverage includes all of the following for 25 years:
- Power Production Guarantee: Also known as a performance guarantee, this ensures your solar system will produce the amount of electricity that’s outlined in your proposal, or ADT will write you a check for the difference.
- Labor Guarantee: This covers any issues with the installation of your system and is also known as a workmanship warranty.
- Panel Module Performance Guarantee: This is what ADT Solar refers to the manufacturer warranty as, and it ensures that any manufacturing defects are repaired or your ineffective panels replaced.
- Enphase Microinverters Guarantee: This backs the performance of your inverters.
Though in recent years other solar companies have started to offer similar guarantees, ADT Solar has been at it since 2008, performing over 30,000 installations across the country.
Facts and Figures: ADT Solar
| EcoWatch Rating |
|---|
| Better Business Bureau (BBB) Rating |
| Year Founded |
| Average Cost ($-$$$$$) |
| Solar Services |
| Brands of Solar Equipment Offered |
| Warranty Coverage |
| 4 |
| A- |
| 2008 |
| $$$ |
| Solar Panels, Solar Batteries, EV Chargers, Energy-Efficiency Upgrades |
| Silfab, Panasonic and others depending on location |
| 25-year all-inclusive warranty |
How Does Google Project Sunroof Work?
Project Sunroof is a smart tool using satellite imagery, 3D modeling and shade calculations from a combination of Google Maps, Google Earth and machine learning technology. However, Google doesn’t work alone in this.
According to its website, Project Sunroof also uses weather and solar savings data from the National Renewable Energy Laboratory (NREL), as well as utility electricity rates, solar costs and tax credit data from other third-party sources.1
Additionally, a machine learning algorithm is trained to recognize solar panels from satellite images and obtain information about which buildings are already using solar panels.
How to Use Google Project Sunroof For Your Home
Google Project Sunroof is pretty user-friendly. You can get a quick, personalized solar analysis for your home with just three simple steps:
- Search for your home
- Add your electric bill information to get a more accurate solar savings estimate
- Compare solar financing options
How to Use Google Project Sunroof For Your City
Another function Google’s Project Sunroof offers is the ability to see solar data for an entire city. For example, in Fresno, California, 96% of rooftops are viable for solar. If all were to reach solar capacity, the carbon offset would be equivalent to taking 278,000 cars off the road each year or planting 21.3 million trees.
How Accurate is Google Project Sunroof?
When it comes to solar potential analysis, Project Sunroof is a helpful tool. However, we’re a little wary about its accuracy when it comes to solar costs and incentives. We say that because — as noted in this screenshot and confirmed by its changelog — a lot of Project Sunroof data hasn’t been updated since 2018.2 Solar prices and incentives vary a lot over the course of a year — never mind four years.
For example, Google estimates that a solar system in Houston, Texas, would be about $24,000 after applying the federal solar tax credit.3 Using internal solar data from 2022, EcoWatch found the average cost of a solar system in Houston to be about $15,228. The discrepancy is likely because the cost of solar in Texas has dropped over the past few years.
While solar calculators are helpful, the only way to get an accurate solar estimate for your home is to get a quote from a certified solar provider.
Do We Recommend Using Google Project Sunroof?
Here’s the thing: Google Project Sunroof is a great tool, but if you’re looking to install rooftop solar panels, we recommend using other resources along with Project Sunroof.
What We Like About Google Project Sunroof
Google Project Sunroof provides helpful information to prospective homeowners about solar potential and the feasibility of adding a solar system. Project Sunroof is a completely free resource, and Google claims it doesn’t make any money off of the tool, which means its sole purpose is to accelerate the growth of solar power to help mitigate carbon emissions. That’s something we can get behind.
Just to give an example of the impact this tool has had, one of the largest rooftop solar installations in Houston was prompted by Project Sunroof naming Houston the “most promising city in the U.S. for solar potential.”4
What We Don’t Like About Google Project Sunroof
While Google Project Sunroof has great intentions and features, it’s not without its flaws. For one, Project Sunroof is also only helpful for those looking for rooftop solar panels and doesn’t provide any data for ground-mounted solar systems.
In our opinion, the biggest flaw of Project Sunroof is that a lot of its information is outdated. As we mentioned earlier, much of the app has not been updated since 2018, but solar energy has become more accessible and affordable since then. As such, Google’s quotes are likely higher than that of a solar installation company near you.
Lastly, Google Project Sunroof cannot connect you to a local solar provider. If you’re interested in getting a free quote for your home solar project, click below.
Comparing authorized solar partners
Average cost
Pros
Cons
BBB Rating
Year founded
Service Area
Brands of Solar Equipment Offered
Warranty Coverage
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- Most efficient panels on the market
- National coverage
- Cradle to Cradle sustainability certification
- Great warranty coverage
- Expensive
- Customer service varies by local dealer
A+Best National Provider1985SunPower Panels25-year all-inclusive warranty
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