TELEVISION SIZE & POWER USAGE?

Most nights while camping, often bookdocking, we watch one movie before bed. With out twin group 27 batteries we are good for three nights until a charge is needed. We run a 19 inch LCD and DV player. Televisions are super cheap now and am pondering moving up to a 28 inch. Am I correct in thinking the power consumption is proportional to size of screen? Will it draw more power and make a difference in our longevity?