Ideal Power, which supplies its battery converters to Sharp’s Smartstorage product in the US, has launched a range of power converters that the company claims are capable of adding grid-tied storage to megawatt-scale solar power projects.
The new 125kW range of power converters adds to Ideal Power’s existing 30kW converters. Ideal Power manufactures converters designed to integrate energy storage with PV and other renewable technologies, using a magnetic ‘hold-and-release’ system.
In an interview with PV Tech Storage in August, Ideal Power president and chief technical officer Paul Bundschuh explained that the storage element of the 30kW converters includes an invector that stores energy magnetically. The new 125kW range includes a three-port hybrid converter and two-port battery converter
“We charge up the energy storage element – in this case it’s a special inductor that stores the energy magnetically, then we disconnect it from the input. While it’s disconnected from the input and output it’s resonant so the voltage and current oscillate and when the voltage matches the output requirement, we just simply release the power.”
The new system is modular and will allow the company to go beyond the capabilities for scaling of its 30kW range, which can integrate energy storage into PV systems of up to 200kW capacity. At present the product serves the commercial and micro-grid markets. The agreement Ideal Power has with Sharp covers the commercial sector in California, designed to cut customers’ demand charges.
Ideal Power claims that in addition to lowering the cost of integration and improving efficiency, its converters can lower costs, utilising its patented form of switching – Power Packet Switching Architecture (PPSA), which does away with the need for an isolation transformer.
“…The hardware topology is actually much simpler than what is used today and what we’ve done really is developed a software-defined power converter,” said Bundschuh.
“In terms of the passive materials, like magnetics and capacitors, we’ve reduced those requirements by about 90% and those materials generally don’t get a lot cheaper every year.”
A California-based company, CODA Energy, has already placed an initial order for the 125kW hybrid converter. CODA Energy manufactures and installs commercial and industrial energy storage products. The company's chief operating officer, Peter Nortman, spoke of a "compelling argument" for grid-tied storage co-located with photovoltaics.
"The mutual benefits of deploying battery storage with PV are well known 'off-grid'. The argument to deploy storage with PV 'on-grid' is perhaps even more compelling to a resilient and sustainable energy future," he said.
"We expect Ideal Power's 3-port hybrid architecture to help us meet our customer's needs in this important market space due to its comprehensive feature set and compact, efficient design."
Ideal Power is NASDAQ-listed under the symbol IWPR. The company claims that through basing its business model on licensing, the use of PPSA can be scaled across several markets, including charging for electric vehicles (EVs) and commercial grid storage as well as the solar PV industry. Ideal Power was also the recipient of a grant worth US$2.5 million from the Advanced Research Projects Agency-Energy (ARPA-E), the US government agency responsible for promoting funding and R&D into advanced energy technologies.
This article has been amended to clarify a technical point.