Some people lack empathy permanently, others switchitoff when they are tired, stressed or impatient telling a child not to bother you because you are working, for example and experience regret for their harsh words when their empathy returns.
Low cost improvements can include replacing incandescent lights with CFL or LED alternatives, master switches to make it easier to switchoff appliances at night, energy monitoring to make it easier to identify waste, draft proofing, and using plants or shade-cloth to keep the summer sun off your home.
