Role of Power Conversion Technology in Solar-Plus-Storage Solutions

High-performance and flexible multiport power converters will be a key enabling component in the energy transition for solar-plus-storage adoption and deployment. The power conversion system is critical when implementing solar power coupled with storage as the efficiency of the conversion will come into play at several stages throughout the system: PV to grid, PV to battery, and battery to grid.

Where do the CE+T Energrid solutions fit into the energy landscape?

The energy landscape has witnessed significant transformation over the past decade with the widespread proliferation of renewables. One of the biggest challenges we face for the continued growth of both utility-scale, and behind-the-meter sited solar is the intermittency of solar generation.

The unpredictable nature of solar power actually stresses the grid in some regions of high-penetration solar where adding additional solar may actually de-stabilize portions of the electrical grid.

Energy storage systems are a key solution to this roadblock – balancing the supply of renewables with the demands of the grid. CE+T energy storage solutions are based on our multiport power converters that enable the direct integration of solar and energy storage in one compact box, supporting both on-grid and off-grid applications. Our solutions are based on a revolutionary method of power conversion that delivers unprecedented flexibility and versatility in a broad range of applications.

Who can benefit the most from CE+T storage solutions?

CE+T Energrid’s storage solutions are based on unique converters for application to all types of projects, such as:

• Grid integrated solar-plus-storage
• Storage-only systems for customer-side demand management
• AC or DC microgrids
• Critical load support and backup power
• Electric vehicle charging stations
• Self-consumption and peak shaving
• Power boosters

As such, those who can benefit the most from CE+T products include renewable project integrators, storage system integrators, utilities and corporate energy managers, or ESCO’s (Energy Service Companies) seeking to deliver lower energy costs while delivering additional value streams to their end customers.

How do CE+T conversion units differ fundamentally from others on the market?

CE+T energy storage solutions represent a fresh approach to power conversion and a technological leap compared to conventional systems. Our PCS units achieve the same electrical isolation as traditional converter technologies at significantly reduced size and complexity.

Our solutions based on the multiport converters are unique. Most existing solar-plus-storage solutions utilize two separate power converters: one dedicated to PV and one dedicated to the battery. The management and integration of these two units is a headache for system integrators, from both a hardware and software point of view. Additionally, the 2-converter approach suffers from efficiency losses as a result of either DC coupling (intermediate DC power bus shared between the two converters) or AC coupling (AC-grid shared between the two converters).

CE+T conversion systems are software-enabled devices, allowing the capabilities of our storage solutions to be tailored to suit specific project requirements, and are easily configured for grid-tied, AC or DC microgrids, or grid-resilient (backup power applications). Multiple units may be paralleled on their AC or DC ports for higher-power applications, utilizing a novel power-sharing algorithm. Lastly, the DC voltage range is wider than most conventional systems, enabling support of almost all high voltage battery technologies.

Why is power conversion so critical for the deployment of solar-plus-storage?

High-performance and flexible multiport power converters will be key enabling component for solar-plus-storage adoption and deployment. The power conversion system is critical when implementing solar power coupled with storage, as the efficiency of conversion will come into play at several stages throughout the system: PV-to-grid, PV-to-battery, and battery-to-grid. Additional factors influence the choice of power conversion technology, including whether the solar-plus-storage system needs to be microgrid-enabled, or if battery storage is being retrofitted to an existing PV system.

Conventional AC, or DC-coupled systems require two separate power converters – one for the battery and another for the PV system. These approaches present significant difficulties for both on-grid and microgrid applications, where external high-speed control loops are required to manage energy-flows between converters and the grid in real-time. CE+T compact multiport converters eliminate this high-speed control requirement, minimizing control complexity. This will accelerate solar-plus-storage adoption and deployment.

Who is your primary customer and why?

As noted above, CE+T appeals to a broad range of system integrators and project developers, who focus on minimizing system design, installation, and ongoing operating costs.

What does the future look like for the power conversion market and what is CE+T growth strategy?
With the recent announcement of Stabiliti™ product family, it is obvious that our storage solutions offering grid-resiliency is increasingly important to many of our integration partners’ end-customers.

Note that 99%+ of today’s deployed PV systems, solar-plus-storage systems, and storage only systems are not grid-resilient. They cannot provide backup power to critical loads when the grid is down. The storage solutions based on the 30kW Stabiliti multiport or the 30kW Stabiliti dual-port offer grid-resiliently, and they can easily be paralleled to support larger system power ratings.

Our storage systems based on the Stabiliti family have created considerable interest not only in the industry, but also in the public sector market segment (municipalities, universities, schools and hospitals), where providing disaster-recovery and shelter-in-place services to local communities. In the past these required expensive, noisy and dirty diesel generators. Now with the CE+T Storage Solutions, the campus microgrid may offset diesel runtime and fuel use by 50% or more at such facilities.