"We are changing that by making sure that more kids, now and in the future, will be kept warm at school by clean energy."
Shaw said there would be more announcements of other schools getting similar funding later this year, and into next year.
The total $200 million fund was one element of the Government $12 billion infrastructure upgrade programme.
Shaw has already announced some projects which would get some of that funding, including eight schools and two hospitals.
The allocation to $50 today brings the total number of school which have received green funding to 26 so far, with a target of 90 in total.
"The Clean Powered Public Service Fund is helping schools, hospitals, universities, and other public organisations to make the switch to clean energy.
Schools that will receive the green funding:
• Te Kura Kaupapa Māori o Wairarapa (Wairarapa)
• Waitaki Boys' High School (Otago)
• Big Rock Primary School (Otago)
• Murihiku Young Parents' Learning Centre (Southland)
• Meremere School (Waikato)
• Miller Avenue School (Waikato)
• Newfield Park School (Southland)
• Manukorihi Intermediate School (Taranaki)
• Ohakune School (Manawatū-Whanganui)
• Greytown School (Wairarapa)
• Ohau School (Manawatū-Whanganui)
• Pukerua Bay School (Wellington)
• Rosebank School (Balclutha) (Otago)
• Dipton School (Southland)
• Edendale Primary School (Southland)
• Invercargill Middle School (Southland)
• Pukerau School (Southland)
• Waikaka School (Southland)
Further schools will be announced later in 2020 and in 2021.