3G sunset for solar panels: Will it affect you?

When you read about cellular networks, you likely automatically think about cell phones – but did you know that these networks also support remote monitoring capabilities of solar systems? In 2022 all major mobile carriers – including AT&T, T-Mobile, and Verizon – are shutting down their 3G networks, impacting several solar system owners in the U.S. who installed 3G modems as a part of their solar panel systems. In this article, we'll explain what you need to know about the 3G shutdown and the steps you can take to upgrade your solar system's cellular modem if your installation is impacted.

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Key takeaways

  • If your solar system has a 3G modem, your system will continue generating electricity.

  • If you don't upgrade to a 4G modem or connect to the Internet, you'll lose monitoring capabilities which may lead to you missing out on valuable incentives like SRECs.

  • You've likely already been contacted by your installer or inverter company if your system is affected; if you're unsure, be sure to reach out to your installer first to see if there are any steps you need to take.

  • 3G shutdowns will also impact owners of some Tesla Model S vehicles who may need to upgrade their modems.

  • To get the best return on investment for your solar system, visit the EnergySage Marketplace.

According to the AARP, about 10 million people in the U.S. still use 3G phones – so why are these networks being phased out? As technology advances, we must free up infrastructure to support new devices by shutting down older services. Specifically, the next generation of cellular communications technology (5G) is now being deployed across the U.S.: 3G networks are being phased out to make room.

5G networks provide a few key benefits over the current widely used 4G networks. In some areas, they'll offer data speeds up to 100 times faster with almost instantaneous response times (i.e., minimal delay). They'll also support additional technological advancements requiring faster data speeds – such as new virtual reality devices and autonomous (self-driving) vehicles.

Any cellular device supported by a 3G network will no longer connect to cellular networks after the 3G shutdowns occur. For some devices, like 3G cell phones, the device will become obsolete. However, with some technologies like solar systems, your system will continue to work after the 3G shutdown – you just won't be able to monitor your system unless you connect it to the Internet. Technologies that may be impacted include:

  • Cell phones

  • Solar systems

  • Medical devices

  • Tablets

  • Smartwatches

  • Vehicles

  • Home security systems

The Federal Communication Commission (FCC) has been working since 2019 to educate the general public about 3G shutdowns – but with everything that's gone on over the past few years, the phaseout may still come as a surprise. While all major carriers will phase out their 3G networks in 2022, the exact date will depend on your mobile carrier. It's important to note that all Sprint networks, including their 4G LTE network, will shut down because of the merger between Sprint and T-Mobile. The major providers have the following stated shutdown dates:

  • AT&T: February 2022

  • Sprint:

    • 3G: March 31, 2022

    • 4G LTE: June 30, 2022

  • T-Mobile: July 1, 2022

  • Verizon: December 31, 2022

First off, we want to reiterate that these 3G shutdowns do not mean your solar system will stop working if a 3G modem supports it; instead, you'll lose the ability to remotely monitor your system if you choose not to upgrade to a 4G modem or connect your system to the Internet, which can have some consequences for your system's payback period:

Performance monitoring

Monitoring your energy consumption and generation is a great way to see how much you spend on electricity bills. However, it's also essential to ensure your system functions properly. Let's say your system experiences an issue – you should be able to identify that there's a problem through your monitoring app because you'll see your production is low. Often, installers may even be able to diagnose and fix the issue remotely. However, when you forgo this monitoring capability, you'll risk missing any system underperformance problems, which could translate to lost savings.


Cellular modems are an integral component of your solar system if you live in an area with performance-based incentives like solar renewable energy certificates (SRECs). These use remote monitoring to track your system's production and compensate you accordingly: you can earn one SREC for every megawatt-hour (MWh) your system generates. However, if you have a 3G modem and choose not to upgrade it or connect to the Internet, you'll stop receiving your quarterly SREC payments, which can substantially increase the expected payback period for your system.

For example, in Massachusetts, the bid price for an SREC is $287. Now let's say you have an 8 kilowatt (kW) solar system, which generates about 8 MWh of electricity each year – this means you'd be losing out on almost $2,300 annually if you have a 3G modem and choose not to upgrade it.

If you want to upgrade your system, you have a few different options. The easiest – and most likely cheapest – option is to follow guidance from your inverter manufacturer. Enphase or SolarEdge inverters are included in over 90 percent of quotes on the EnergySage Marketplace, so we'll explain how each company is helping you upgrade your modem. In some instances, as described in greater detail below, you may also be able to connect your system to the Internet instead of upgrading your modem.


If you own a solar system with Enphase microinverters, you've likely already heard from Enphase directly if you have a 3G modem. Enphase's upgrade program has been in progress for a few months now, and they've already upgraded several people to 4G modems. If you're unsure if your modem needs to be upgraded, check out Enphase's guidelines for finding your modem information; if your system was installed before 2018, your modem will most likely need to be upgraded.

You have a few options if you're in the group of people who haven't yet upgraded their modems. First, in December 2021, Enphase acquired 365 Pronto, a technology and operations & maintenance company that will be providing installations of these upgraded modems for Enphase systems. On the other hand, if you want to do the installation yourself, Enphase has created a video and FAQ for how to DIY the replacement. Enphase's replacement modem is listed for $381, but this price tag may be lower if you have a relatively new system.


If your system has SolarEdge string inverters, you've most likely received an email from either SolarEdge directly or your original installer (especially if you installed your system through a larger company). If you want to double-check that 3G shutdowns do not impact your system, you can call your installer or email SolarEdge directly.

Still need to upgrade the modem in your SolarEdge system? If you want someone to perform the installation, contact your original installer first. If you can't contact your installer, you can use this form to contact a SolarEdge-authorized provider. You can also install it by following this video (it should take about 20 minutes), but you'll need to purchase the new modem through a distributor. Because SolarEdge doesn't sell their modems directly to customers, there is no listed price point – you'll have to discuss costs with your installer or distributor.

If you replace your modem in your SolarEdge system, your communications plan will automatically be extended to December 31, 2028.

Unfortunately, in the case of both Enphase and SolarEdge, the warranty doesn't cover the cost of the replacement modem – except SolarEdge's 12-year modems, which are being provided by SolarEdge free of charge (but labor is still not included). However, in the case of Enphase, the cost of the new modem may be pro-rated depending on the age of your current system.

You don't have to upgrade your modem – for both Enphase and SolarEdge systems, you can connect your system to the Internet. Enphase provides a helpful guide with step-by-step instructions for connecting to your home's WiFi. For SolarEdge, you can connect your system with an Ethernet cable or a wireless card. You'll need an installer to make the connection because it requires removing the inverter cover.

It's important to note that if you connect your system to the Internet instead of upgrading to a 4G cellular modem, you may lose out on some monitoring benefits – and potentially SRECs – if your connection is unstable.

Many vehicles, including electric vehicles (EVs), will be affected by the 3G shutdown. In the case of Tesla, Model S vehicles built before June 2015 likely include 3G modems that will no longer work. According to Tesla, if you choose not to upgrade your modem, some of the features you'll lose access to include:

  • Roadside assistance to remotely unlock your vehicle

  • Cabin preconditioning, vehicle location, and other mobile app capabilities

  • Navigation, maps, live traffic updates, Supercharger availability, online music streaming, and other informational and entertainment features

  • Over-the-air software updates

You'll still have access to these features when connected to WiFi – but considering you're generally not within WiFi range when driving your Tesla, you'll probably want to upgrade your modem to retain access to these features. Upgrading the modem for your Tesla will cost $200 (including installation) plus any applicable taxes.

Are you looking to install a solar system? The good news is that 4G modems won't become obsolete anytime in the near future, so you can feel confident having the most up-to-date solar technology. The best way to maximize your return on investment is to compare quotes: on the EnergySage Marketplace, you'll receive custom quotes from installers near you to find and install a system that meets your needs at the right price.

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