Electrical Power System Technology Permitting the Feeding to the Grid of Large Amounts of Renewable Energy

For decarbonization, it is expected that a large amount of renewable energy will be introduced to the electric power system. In order to promote the introduction of renewable energy, JGC is presently engaged in 1) Virtual Power Plant (VPP) which bundles the demand side of distributed power sources (DER: Distributed Energy Resources) and operates as one power supply, and 2) solar energy storage that smooths the output of solar photovoltaic power.

1. Virtual Power Plant (VPP)

Taken as a measure to reduce greenhouse gases, the rapid introduction of photovoltaic power generation etc. has resulted in the appearance of various problems affecting the electric power system, such as output fluctuations and generation of surplus power spikes. In order to stabilize the electric power system, the ability to adjustthe supply of power through the use of gas thermal power generation etc. is required, but this results in the burden of costs for maintaining thermal power generation facilities. For this reason, it is necessary to have a technology to achieve continuous renewable energy introduction and power system stabilization at low cost.

As an aggregator of dispersed power sources, JGC developed a VPP capable of operating DER such as solar power generators, storage batteries, and household generators as a single virtual power source. The VPP can adjust demand to stabilize the electric power system by controlling DER in accordance with demand response instructions from power transmitters and distributors. Moreover, we will share our profits among clients who can provide us with DER in accordance with their capacity (kW).

2. Solar Storage

The direct current (DC) power obtained from the solar panels (PV) is converted to alternating current (AC) by a power conditioner (PCS) and supplied to the system. In recent years, output curtailment control is being carried out, and the amount of carbon dioxide reduction by solar power generation also decreases due to the output suppression control.

Solar storage developed by JGC (PV SMOOTHERTM) has a storage battery connected to the DC bus with suppressed power while controlling the PV MPPT (Maximum Power Point Tracking), in addition to storing power and recovering power, overloading (The amount of PV generation larger than the PCS output) is also collected in the storage battery. In addition, since the power recovery unit according to the present technology operates independently of the PCS, no technical cooperation with the PCS is required, so it can be attached to the PCS of any manufacturer. In summary, JGC Solar Storage (PV SMOOTHERTM) offers the following value:

  • Improvement of total power generation by charging overloaded electricity
  • Improvement of the total electricity generation amount by charging electric power at the time of output control
  • Smoothing of photovoltaic power output