Taipower denies solar power drives up electricity bills with separate metering

Recently, several businesses in the Taitung area reported that after installing solar photovoltaic systems, their electricity bills increased significantly, with some even experiencing a sudden surge in electricity costs. General business owners mistakenly believed that the power generation of their own rooftops directly affected their electricity billing, raising doubts about the economic benefits of solar photovoltaics. In response to such complaints, Taiwan Power Company (Taipower) stated today that the electricity calculation for the photovoltaic system and the consumer side are separate, and there is no direct correlation between the two.

According to Taipower's explanation, photovoltaic systems installed on business rooftops are equipped with dedicated bidirectional meters specifically designed to measure the system's own power generation and the amount of electricity fed back into the power grid. Meanwhile, the electricity consumption of the business is handled by another bidirectional meter, which records only the electricity actually consumed. This dual-meter design allows power generation and consumption data to be clearly separated, preventing misunderstandings caused by generation amounts being factored into electricity bills. Taipower emphasized that if a business experiences abnormal electricity bills, it should first inspect the meter readings and electricity consumption behavior on the consumer side rather than the power generation of the photovoltaic system.

This approach aligns with the Renewable Energy Development Act promoted in Taiwan since 2016, which encourages the private sector to independently install renewable energy facilities such as solar and wind power, adopting a mechanism of "self-generation for self-consumption, with surplus power bought back." To ensure transparency and fairness in power transactions, Taipower uniformly utilizes bidirectional meters nationwide to simultaneously record users' incoming and outgoing electricity volumes, and settles accounts in accordance with government-established feed-in tariffs. This system has been proven in most cases to effectively separate generation and consumption billing, avoiding the issue of double counting.

However, the electricity rate structure for commercial users is inherently complex. Taipower applies time-of-use electricity rates and basic electricity charges to different categories of users, and commercial electricity demand often exhibits fluctuating characteristics between peak and off-peak hours. If a business still requires a large amount of electricity during peak hours, and the power generation cannot fully cover the demand even with rooftop generation equipment, considerable electricity expenses will still be incurred. Additionally, if some business owners fail to promptly adjust the operating modes of their power-using equipment—such as the operating hours of air conditioning and refrigeration units—after installing photovoltaic systems, it may also lead to the phenomenon of seemingly soaring electricity bills.

From an industrial perspective, the payback period for photovoltaic investments is typically calculated over many years, and short-term electricity price fluctuations should not be the sole indicator for evaluating their benefits. The government and Taipower also continue to promote energy management platforms to help users monitor generation and consumption in real time and provide energy-saving advice, hoping to reduce similar misunderstandings through information transparency. If demand response mechanisms on the consumer side can be further improved in the future to allow solar power generation to more effectively match electricity demand, it will help enhance the overall benefits of renewable energy.

In summary, the electricity bill abnormalities perceived by Taitung businesses are not directly caused by photovoltaic systems, but rather result from actual consumption on the consumer side and the billing method. Taipower's bidirectional meter system is already capable of clearly distinguishing between power generation and electricity consumption, ensuring fair settlement for photovoltaic investments. If businesses wish to lower their electricity bills, they should still start with electricity consumption behavior, equipment management, and energy management systems to truly maximize the energy-saving and carbon-reduction benefits of solar energy.