Not completely impractical as much as not <i>economically advantageous</i> at this point in time.<p>You have to invest money to install solar panels; the expectation is that you can make that money back either by saving on running costs or by selling back electricity. If your running costs are projected to be the same (not worse, <i>the same</i>) and selling back is not profitable, then the fixed installation costs make the investment overall unprofitable, and the industry dies.