Efficient Hybrid System for DC Grid Applications

Overview

An efficient photovoltaic PV-battery hybrid system for DC grid applications, which integrate four technologies (Photovoltaic, Energy storage, Direct current and Flexible management system) to improve system efficiency

Technical name of innovation

Research completion

31/07/2025

Commercialisation opportunities

IP licensing, Technology co-development

Problem addressed

Problems of nowadays PV - battery energy storage systems including 1) Unstable solar power is a kind of risk causes unstable power grid operation and cannot support the power demand of nighttime human activities 2) light load inefficient power conversion and 3) Slow protection of traditional circuit breakers cannot meet DC system requirement

Innovation

To power a home / building by Direct Current (DC) instead of nowadays Alternating Current (AC). DC power systems rely on centralized, higher efficiency devices to convert AC to DC power and then distribute to various loads, which can reduce the energy loss dramatically
SiC-based system with Adaptive Multilevel Converter (AMC) structure to achieve 98%+ efficiency from 20% load
Solid-state DC Circuit Breaker (SDB) with fault identification in microsecond µs, 100 times faster than traditional circuit breakers

Key impact

Total project amount HK$16.8M with contribution of HK$8.6M
DC building power infrastructure technologies will reduce 25% of electricity loss and ~40% cable cost as compared to nowadays AC building power infrastructure
Estimated can save 79,000 kWh annually for 10,000m² , equivalent to ~39.5 Tons CO₂ emission (~50% carbon reduction)

Application