How to Use FlexConnect to Open Truck Charging Depots Years Ahead of the Grid

Getting a grid connection for a new charging depot is the single biggest hurdle for fleet electrification. In capacity-constrained parts of California, a site can request the power it needs and be told the upgrade won't be ready for years.

WattEV just showed there's another way.

3.6 MW on a 1 MW connection: WattEV's Fresno depot

On June 30, 2026, WattEV opened a heavy-duty electric truck charging depot on the Highway 99 corridor in Fresno, roughly two years before the grid upgrade that would normally have gated it .

WattEV needed 3.6 MW to run the site. Only about 1 MW of firm capacity was actually available on the local grid. Under a traditional interconnection, the depot would have waited for a capacity upgrade at least until 2028 or 2029. Instead, PG&E's FlexConnect program paired with flexible load management unlocked access to the full 3.6 MW during most hours of the year, and the site opened now.

This site is built for serious throughput: seven Megawatt Charging System (MCS) chargers with dwell times of 30 minutes or less, plus fifteen 240 kW CCS chargers. It's WattEV's seventh depot in California and the first of a planned Northern California network.

PG&E is proud to (…) deliver faster paths to power for large-load customers

Josh Simes, Regional Vice President, Central Valley PG&E (News Announcement Fresno Site)

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So how do you get the same outcome for your site? Here's the path, step by step.

1. Understand FlexConnect

FlexConnect is PG&E's flexible interconnection program. It exists to solve a specific problem: high-demand sites (EV charging depots, large industrial loads, data centers) keep hitting local capacity limits that would otherwise take a full grid upgrade, and years, to relieve.

Traditional interconnection is built on worst-case planning. The utility studies your site and guarantees you the full requested capacity every hour of every day, 365 days a year. If the local grid can't support that today, you wait for the upgrade.

Instead of a fixed guarantee, FlexConnect gives you dynamic load limits. You accept a limited connection during the hours when the grid is actually constrained and in exchange you connect far sooner, often without waiting on the upgrade at all.

For most FlexConnect customers, full capacity is still available the large majority of hours in the year. You're only trimming during the windows when the grid genuinely needs you to.

Mechanically, PG&E's Distributed Energy Resource Management System (DERMS) sends your site automated day-ahead hourly limits. Your job is to receive those limits and turn them into real load reduction on-site — and to fail safe to a preset limit if communication with the utility ever drops. That last part is why PG&E gates participation on certified technology like Ampcontrol.

2. Find out how big your capacity gap is

Before any of this applies, you apply for the connection and PG&E runs a pre-assessment. If there's a constraint, they issue a load limit letter spelling out the firm capacity available today and the timeline for the upgrades you'd otherwise wait on.

If your firm capacity is close to what you need, flexible interconnection may not be worth the effort. If there's a big gap as seen in Fresno, FlexConnect is how you close it without losing years.

3. Choose a certified vendor

Your energy management system has to speak the utility's language: IEEE 2030.5 CSIP, the mature, cyber-secure protocol PG&E uses to talk to customer equipment. And it has to pass PG&E's interoperability testing before it can control load under the program.

There are three ways in:

• Use an approved vendor. Pick from PG&E's list of vendors that have already cleared CSIP interoperability testing and integrate with the vendor.
• Bring your own vendor. If your platform supports IEEE 2030.5 CSIP, your provider can get CSIP certified and complete PG&E's testing process to qualify.
• Plug and play. If your charger or charging-management platform is an approved vendor, you can participate directly.

Very few vendors have actually completed the control-application testing FlexConnect requires. Choosing a vendor that's already certified means you skip a one-time integration effort that can be a real barrier to participation, especially for smaller operators.

This is where Ampcontrol comes in. Ampcontrol is certified for IEEE 2030.5 CSIP and built to operate under dynamic grid programs like FlexConnect. Our AmpEdge controller receives PG&E's day-ahead hourly limits, holds the site within them in real time, and handles the failsafe behavior the utility requires if communication is lost.

Just as usefully, it speaks the mix of protocols a real depot runs on. Chargers, batteries, and inverters often talk OCPP, Modbus, and MQTT. AmpEdge manages them as one coordinated system rather than three disconnected ones.

4. Energize now and upgrade later

With a certified vendor in place and a signed FlexConnect participation agreement, the site can come online against available capacity while the longer-term upgrade proceeds in the background. You start operating today instead of waiting for years. Once the grid has been upgraded, you can run your site on the full connection all hours of the year.

Open your depot years ahead of the grid

If your site is stuck behind a capacity constraint, FlexConnect may be your fastest path to power. Ampcontrol is a certified FlexConnect vendor, and we take you from load limit letter to live site (as we did in Fresno!").