Lower level LED lights will be installed in the outer regions of Dunedin in a bid to protect sensitive ecological areas.
The Dunedin City Council will install 2200K (Kelvin) LED lights in about 765 street lights in some part of Waikouaiti, Aramoana and the Otago Peninsula.
The rest of Dunedin has 3000K LEDs.
Kelvin is used to measure and describe the colour temperature of a light source or how warm or cool it looks.
While the lights will look like the current ones installed, the lower Kelvin levels will minimise blue light and light pollution.
Council asset and commercial manager Merrin Dougherty said the changed followed feedback from residents.
"We are installing 2200K LED lights to protect these ecological sensitive areas and to also preserve night sky viewing."
A study into blue light by The Royal Society Te Apārangi found artificial light can disrupt the body clocks of wildlife, affect plant growth, pollination, reproduction, and animal patterns.
The lower Kelvin lights will be less energy efficient and will cost more to maintain than the current lights.
The council will be able to brighten or dim the lights as needed through a central management system.
The project is a joint initiative between the council and the Transport Agency, which has a minimum standard of 4000K.
About $15 million is expected to cover costs including street light pole renewal - the Transport Agency is funding 85 percent of the initiative.
The work expected to be finished by mid 2021.