Over on the Hohm forums, user Matthew Martin mentioned challenges for renters to save energy. (Adding insulation, for instance, is probably a no-go.) Thankfully, the Gandalf-like energy experts at WSU weighed in with tips to save energy in your apartment. (Want your home energy question answered? Email us!)

Q. What can people in apartments do to save energy and lower their energy bills?

A. Here are some easy ways to save energy, organized by cost. Apartment dwellers and home renters are usually under the auspices of the owner or management (and state tenant laws), so be mindful of that. Additionally, programs to help low-income dwellers with the cost of efficiency upgrades may be available (with owner permission).

Free ways to save energy:

• Use a microwave instead of the oven or stove. Microwaves can cut energy use by up to 80%!
• Turn off lights when you aren't using them! Lighting makes up about 15% of home energy use.
• Wash full loads of dishes and clothes.
• Wear lighter clothes in the summer so you can adjust the thermostat a few degrees—each degree could save you 3% on cooling!
• Turn everything off when you go to bed (including the computer) and adjust the temperature 5 to 15 degrees.
• During the summer, use passive solar cooling strategies. This includes closing window blinds during summer days (if windows face south/west) to prevent excess heat from building up. Open windows in the evening to use natural ventilation instead of the A/C and help lower your cooling costs.
• During the winter, use passive solar heating strategies (translation: keep blinds open to allow the sun's heat to build up instead of using your heater).

Under $10:

• Replace incandescent bulbs with energy-efficient lighting like compact fluorescent lamps (CFLs) or light emitting diodes (LEDs). Energy Star CFLs use 75 percent less energy than standard bulbs!
• Use a power strip to turn all of your appliances and electronics off at once, or unplug them manually! (Turn off your computer first.) Electronics with a remote like TVs, stereos, or cable and satellite boxes are put on standby, not turned off, when you hit the remote—and could still be using energy ("energy vampires").

More spendy:

• Work with your landlord or management to get all the apartments weatherized with caulking and weatherstripping for doors and windows. Tenants will want to stay because it’s comfortable!
• Pick Energy Star products when you're buying new ones. Energy Star gives their label to computers, DVD players, dehumidifiers...you name it!
• Condo residents may have more control over their clothes washer model—pick an Energy Star clothes washer.

For more reading, check out the Department of Energy's ideas for renters to save energy.

Image: The Welsh Poppy