When Innovation Meets Real-World Constraints 

The Challenge: A closed landfill site in Kingston, Massachusetts hosts an ambitious renewable energy project—a 2.6 MW solar array paired with a 1 MW battery storage system, all feeding through a single 882 kW inverter to the grid. The configuration creates a unique problem: how do you maximize the value of excess solar generation when your grid connection can only handle one megawatt at a time and when you can only charge the battery from solar generation? 

 For Customized Energy Solutions, this challenge became an opportunity to innovate. 

The Complexity Behind the Innovation 

The Kingston project, owned by Kearsarge Kingston LLC, required solving multiple variables simultaneously: 

  • Solar variability: Cloud cover and sun angles cause second-by-second fluctuations in generation 
  • Interconnection limits: Only 882kW can flow to the grid at any given time 
  • Battery optimization: Charging must come exclusively from solar to maintain tax credit eligibility 
  • Market dynamics: Real-time pricing determines when to export versus when to store 

CES saw an opportunity to improve upon the base battery management system at the site, to increase the amount of solar that could be captured from otherwise lost energy and then released to the grid when inverter capability allows. 

Engineering a Dynamic Response 

CES developed a sophisticated control algorithm that dynamically manages the interplay between solar generation, battery charging, and grid export—all while respecting the 882-kW interconnection limit. 

“When you’re optimizing these hybrid assets, the optimization engine is only one piece,” explains Matt Lollini, who led the technical implementation team. “As the MW output of the solar asset deviates from your forecast, which it inevitably will, the control algorithm refines the control of the asset to ensure it can deliver as close as possible to the original optimization output.” 

The innovation works through sophisticated real-time monitoring and dynamic adjustment. CES’s proprietary algorithm continuously balances multiple variables: solar output fluctuations caused by weather conditions, the 882-kW interconnection constraint, battery state of charge, and wholesale market pricing signals. The system makes autonomous decisions multiple times per minute, ensuring maximum value extraction while maintaining compliance with all technical and regulatory requirements. 

Adapting Existing Technology for New Challenges 

To make this work, CES adapted its PowerGreen controller—originally designed to manage peak demand for large commercial and industrial customers—for front-of-the-meter renewable energy applications. 

“This was the first time CES used it for controlling a non-behind-of-the-meter project,” explains Matt Lollini. “We had to completely reimagine how the controller operates, but the core control principles translated perfectly to this new challenge.” 

The innovation demonstrates CES’s broader capability to adapt technologies for emerging applications. Erik Paulson, CES’s VP of Wholesale Market Services, notes that the company applies similar creative problem-solving across a diverse portfolio: “We have a number of unique assets for which we provide market operations with a focus on helping the client owner achieve optimal market revenue. This includes renewable resources, energy storage, demand response, and innovative applications that help balance grid needs with market opportunities.  This is all in addition to the more bread and butter resources we manage, mostly wind and solar assets but including just about everythingexcept nuclear, to the tune of 30,000MWs, representing the company’s commitment to solving complex energy challenges regardless of the resource type.” 

The result is a system that operates in three distinct modes: 

Discharge Mode: When solar generation has ended for the day, the battery discharges to capture high-value evening pricing periods 

Clipped Solar Charging: The battery charges only from excess solar above the 1 MW export limit, maintaining maximum grid output 

Full Charging: When wholesale prices are extremely low or negative, the system prioritizes battery charging even if it means reducing grid exports 

From One Project to a Portfolio 

The success at Kingston demonstrated CES’s ability to solve complex renewable energy challenges. This technical breakthrough became the foundation for additional projects.  

Today, CES manages over 50 projects across ISO New England, representing a diverse portfolio of solar, battery storage, and hybrid renewable resources. In several cases, CES replaced incumbent operators who couldn’t deliver the optimization performance needed.  

“What sets us apart is our ability to innovate rapidly when clients face unique challenges,” notes Bill Schofield, VP of Future Grid Services, who has been with CES since 2002. “This project exemplifies our culture—we choose to be on the cutting edge and take particular pride in helping our clients figure out how new technology can effectively participate in the markets.” 

The Competitive Advantage 

In today’s renewable energy landscape, interconnection constraints are increasingly common. As more solar and storage projects seek grid access, developers face limitations that can make or break project economics. 

CES’s Kingston solution offers a blueprint for maximizing the value of constrained hybrid resources. By combining sophisticated optimization algorithms with dynamic asset-level control, CES enables project owners to: 

  • Maintain maximum grid export during economically valuable hours 
  • Preserve tax credit eligibility by ensuring battery charging comes exclusively from renewable sources 
  • Capture additional revenue through participation in Massachusetts’ Clean Peak program 
  • Adapt in real-time to changing weather, market conditions, and operational constraints 

Why This Matters 

As the energy transition accelerates, the industry will face increasingly complex technical challenges. Hybrid renewable resources, constrained interconnections for both generation/storage resources as well as large consumers such as data centers, and evolving market rules require operators who can do more than follow standard procedures. 

The Kingston project demonstrates CES’s core strength: the ability to understand complex problems, develop innovative solutions, and deploy them rapidly to deliver measurable results. 

“Energy storage and hybrid resources aren’t just about having batteries or solar panels,” Paulson explains. “They’re about having the expertise, the technology, and the creative problem-solving ability to make those assets work together optimally under real-world constraints.” 

Looking Forward 

With nearly 1,000 MW of utility-scale battery storage under management and a growing portfolio of hybrid renewable resources, CES continues to push the boundaries of what’spossible in storage hybrid optimization. 

The Kingston project represents just one example of how CES combines deep market knowledge, advanced technology, and innovative thinking to help clients navigate the complexities of modern energy markets. 

For project developers and asset owners facing similar challenges—whether interconnection constraints, complex market rules, or novel resource configurations—the message is clear: CES can help.