Water naturally heated by the earth will be pumped from 230m underground to heat 150 homes.
A yellow "be aware" weather warning for ice is in place across most of the country.
A network of live webcams is set up around Barry Island to promote winter tourism.
Leigh Halfpenny is fit for Scarlets' European Champions Cup clash with Toulon at Parc y Scarlets on Saturday (17:30 GMT).
Double Olympic champion Jade Jones is hoping to cash in by winning the inaugural World Taekwondo Grand Slam Series in China.
South Wales Argus
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