Transpower releases research on Solar PV

11 December 2017

Transpower today released research that finds New Zealand’s power system is in a good position to enable a significant increase in renewable electricity generated from solar photovoltaic (PV) panels.

The amount of solar PV on the rooftops of homes and businesses is increasing. The research examined how significant amounts of this distributed, variable electricity generation could affect the operation of the National Grid as it displaces generation from other sources.

General Manager System Operator John Clarke said the research results were positive.

“Overall, we found that the existing New Zealand power system can accommodate significant levels of solar PV in addition to the present generation mix and demand for electricity. This is due to the inherent capability of the system to provide two-way power flows (from north to south, and south to north) and for hydro generation to cover short-term variations in electricity generation from other sources.”

“We did this research to understand how to avoid potential difficulties and ensure that the National Grid will enable electricity consumers to use the technologies they choose,” he said. “Our research did not consider specific impacts for local distribution networks where there may be issues we have not considered. We focused on the overall transmission system and power system operation.”

Clarke said that some countries have experienced difficulties managing their power systems when solar PV has increased significantly. “Currently New Zealand has less than 1% of its electricity generated by solar PV, but this is increasing. Our research has helped us identify when further studies will be required, and this is likely to be as installed solar PV approaches 1,000 Megawatts or around 16 times that installed today.”

The studies also highlighted the importance of inverter technology.

“Inverters are the devices that convert solar irradiance to electricity that you can use in your home,” Clarke added. “There is a standard for inverter requirements, and our studies found that if non-compliant inverters are sold and used in New Zealand, this will pose additional limitations and costs for the power system in the future.”

“We have been undertaking a research programme investigating how emerging technologies will impact the power system. We have assessed international observations in the New Zealand context, to ensure we can remain agile and responsive to the evolving energy industry and environment. This solar report is the second in our programme of work,” he said.

Transmission Tomorrow, a perspective on the future role of the energy industry was released last year. This document and other research is available at 


For further information, please contact:

Rebecca Wilson, Corporate Communications Manager, 04 590 6695 or 021 578 608