Hope everyone's having a good week. I'm working on a complex audit for a manufacturing client in Grand Rapids with both solar panels and a Tesla battery storage system. Consumers Energy is billing them under Schedule GS-2 with demand charges, but they're not properly crediting the battery's peak shaving capability. The customer's demand charge went from $180/month pre-battery to $165/month post-battery, but based on the load profile data, it should be closer to $95/month. Anyone else seeing Consumers Energy struggle with battery storage billing?
Consumers Energy Battery Storage Demand Charge Issues
Tina, this is becoming a common issue as battery storage proliferates. The problem is most utility billing systems aren't sophisticated enough to properly track the peak shaving benefits in real-time. They're still calculating demand charges based on gross consumption rather than net demand after battery discharge. Have you been able to get interval data from the battery management system to prove the peak reduction?
Randy, yes we have 15-minute interval data from both the utility meter and the Tesla Powerpack system. The data clearly shows the battery is shaving 45kW of peak demand during the 2-6pm window when Consumers calculates their monthly demand charge. But their billing system is apparently only looking at the utility meter data and ignoring the storage dispatch. The customer is getting screwed out of about $70/month in demand charge savings.
This sounds exactly like an issue we had with WE Energies up here in Wisconsin. Their Schedule Cg-5 demand billing couldn't properly account for behind-the-meter battery storage. The solution was getting their engineering department to manually review the interval data and issue billing adjustments. But it took threatening a PSC complaint to get them to take it seriously. Have you tried escalating beyond customer service?
Dan, we're preparing to escalate to MPSC if needed. The frustrating part is Consumers Energy promotes their battery storage incentive programs, but their billing department can't properly handle the resulting load profiles. It's like the left hand doesn't know what the right hand is doing. The client is considering disconnecting the battery system entirely if this doesn't get resolved soon.
Tina, don't let them disconnect that system! We had a similar client in Memphis threaten the same thing with MLGW. The key was documenting the exact methodology error in their billing system and proposing a specific solution. In our case, we showed them how to modify their demand calculation to account for storage dispatch. Took 4 months, but the client got $2,800 in retroactive credits and proper going-forward billing.
Calvin's right about proposing specific solutions. Utilities often want to fix the problem but don't know how. We created a detailed technical memo for KCP&L explaining exactly how their billing system should handle battery storage under Schedule LGS. Included sample calculations, interval data analysis, and proposed tariff language modifications. They implemented our recommendations and it solved the problem for all their battery storage customers.
Kevin, that's exactly the approach I'm taking. Working on a technical brief that shows Consumers Energy exactly where their billing system is failing and how to fix it. The client's engineer is helping with the battery dispatch data analysis. If we can solve this for one customer, hopefully it helps all their battery storage customers. This is definitely the future of utility billing - they need to get this right.
Tina, please keep us posted on how this resolves. I'm seeing more battery storage billing issues across multiple utilities, and we need documented solutions that work. The regulatory landscape is still catching up to the technology. Your technical brief approach could become a template for similar cases nationwide.
Randy, absolutely will share the outcome. We're also working with the client's attorney to document potential class action implications if Consumers Energy has been systematically under-crediting battery storage customers. This could affect hundreds of customers across Michigan. The stakes are getting higher than just one billing dispute.
Following this thread with great interest. Ameren Illinois is rolling out battery storage incentives here in Springfield, and I want to be prepared for similar billing issues. Tina, would you be willing to share your technical brief template once you're done? This is exactly the kind of knowledge sharing that makes this forum valuable. The utilities are definitely not prepared for the complexity of distributed energy resources.