REMBERT (AP) -- A state prison will soon be home to South Carolina's largest dairy under one roof.

A $7 million expansion will quadruple the herd at a prison farm and allow the state to sell millions of gallons of excess milk.

South Carolina's three prison farms already save taxpayers more than $600,000 annually. Inmates work to produce all the milk, eggs and grits -- and some vegetables -- served to 24,000 prisoners statewide.

It's largely why the state spends a paltry $1.51 daily on three meals per inmate.

Officials hope the new dairy at Wateree River Correctional Institution will cover all farm costs. The expanded dairy opening in January will eventually house 1,000 cows, up from 220.

Inmates who qualify can reduce their sentences through farm work.

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