Ask GoodWe! What are the points to consider for repowering by exchanging power conditioners?
Ten years have passed since the enforcement of FIT, and repowering by exchanging power conditioners has begun. We asked Mr. Hisao Nakai, the country manager of Good We Japan, a manufacturer specializing in power conditioners, what to be careful about when exchanging power conditioners.
Replacing with a new power conditioner
For the model that held the point
It's been 10 years since the feed-in tariff (FIT) started. There will be many projects that started operation around 2013 and refrained from regular inspections of centralized power conditioners and replacement of parts. Therefore, I would like to consider repowering by exchanging the power conditioner.
Hisao Nakai of Good We Japan, a manufacturer specializing in power conditioners, says, "It takes a lot of time and effort to change the layout of the panel, but it is relatively easy if you just reconnect the input of the power conditioner." If the panels are to be replaced, it may be necessary to replace the gantry including the foundation.
"If the purchase price is high and the initial cost has already been recovered, I think it is possible to raise the cost of replacing the power conditioner," (Mr. Nakai).
However, there are some points in exchanging power conditioners.
"Old-fashioned power conditioners generally had a DC voltage of 650V, but the current mainstream is 1000V or higher. Unless the MPPT has a wide range of motion, it cannot be replaced as it is," says Mr. Nakai.
When using an old centralized power conditioner with high-voltage interconnection, maintenance costs are often high. However, if you replace it with a new model, you can extend the product warranty, support remote output control, and reduce operating costs.
In fact, at the 2 MW field solar power plant under the jurisdiction of Shikoku Electric Power Co., Inc., efforts have begun to gradually replace the power conditioners that manufacturers have withdrawn from the market with their products.
Let's increase the profitability of the solar power plant by exchanging smart power conditioners that hold down the points.
Solar power plants that should be considered for power conditioner replacement
□ High-voltage interconnection using an old centralized power conditioner
□ Power conditioner manufacturer has withdrawn from the Japanese market
□ The warranty period of the power conditioner has expired or is about to end.
□ The decrease in power generation exceeds the initial forecast
□ The electric power company has requested the addition of an output control device.
Benefits of replacing the power conditioner
● Increased power generation with high conversion efficiency
● Easy maintenance with string monitoring
● Free warranty for 5 years, extension is also possible
● Distributed power conditioner to disperse the risk of power generation loss
etc.
Points of repowering by exchanging power conditioners
① Is the starting voltage and MPPT operating range sufficient?
The lower the starting voltage of the power conditioner and the wider the operating range of the MPPT, the more the power conditioner can be replaced with the existing module layout.
② Is the AC output voltage versatile?
In order to use the existing transformer, a power conditioner with a versatile AC output voltage is advantageous.
③ Whether remote output control is possible
Consideration of output suppression is in progress outside the Kyushu Electric Power jurisdiction. If the model can control the output remotely, the labor and cost of dealing with it and the loss of power sales can be suppressed.
DATA
SMT series 33kW / 40kW
The maximum DC input voltage is 1100V and the starting voltage is 180V. High-performance power conditioner with maximum conversion efficiency of 98.8% equipped with MPPT of 4 circuits. With a compact design weighing only 40 kg, it can be used for self-consumption systems installed on the roof.
