My gelding is a 17/17.1 thoroughbred. He's going on nine next month, and has been in medium work (3-4 days a week, 50 min - 1 hr long sessions) over the winter. He gets 12 hr turnout, 5am to 5pm (0500-1700) and goes through about 25 - 30 lbs of hay: he gets 10 lbs of alfalfa (2 string bales - medium flakes) and 15-20 lbs of grass/orchard mix (3 string bales - large flakes). He gets a grass flake at 5am, an alfalfa and a grass at 7am, another small grass flake at noon, then two alfalfa (or one large) and a grass at 6pm. All his hay is put in a 1" opening hay net for a 'slow feed' effect. He usually finishes his hay net about an hour before the next feeding, so he eats almost continuously. He also is on 3 oz of Renew Gold in the am, and 5oz at dinner time (plus his Rx allergy medication, a joint medication, and hoof/coat supplement).
He grows almost no coat, so wears a light sheet almost year round (save for the rare 65* degree (Fahrenheit) or higher temps we get in june/july/august) and if it drops below the low 30s he gets a medium weight added, particularly at night. If it gets into the low 20s or teens, which it did a handful of times this winter, I add a light hood too.
"The horse, with beauty unsurpassed, strength immeasurable, and grace unlike any other still remains humble enough to carry a man upon his back." -Wise and Greatful