Energy efficiency
None of this is expert advice. It's what people worked out for themselves, usually the hard way — what actually helped, and what they'd tell someone standing where you are. Take what fits and leave the rest.
If you only read a few
Attach aluminum foil to sun-facing windows, then shut the blinds.
Foil reflects more heat than blinds alone.
- Wrapping the foil around cardboard may be necessary, as foil alone might make things worse.
- It does not look pretty.
4 people, independently
Focus on having AC over saving money by working extra shifts if you live in a place where it is too hot without it.
It is too hot to go without AC in this location.
- One person's approach in Texas; involves working an extra shift per week.
one person who lived it
Keep ceiling fans running in winter only if you have high ceilings or vaulted ceilings with a large temperature discrepancy between floor and ceiling.
In typical 10-foot ceiling rooms, the effect isn't dramatic, and moving air generally feels cold.
- Does not work well in typical 10ft ceiling rooms.
3 people, independently
- Keep in mind that ceiling fans might not lower the temperature much in small spaces or rooms with low ceilings.3
Hang large towels soaked in water on a clothing rack and aim a fan through them to create a cool air tunnel, provided the humidity is not excessively high.
This acts as an instant swamp cooler.
- This method is effective only if you do not live in an area with insanely muggy conditions (more than 50% humidity).
one person who lived it
If you need to cool a single room, buy a small window AC unit for $125 or less.
The power bill increase is minimal and considered worth it by one user.
one person who lived it
air, windows, heat, room62
Leave space at the top of water containers before freezing to allow for expansion and prevent bursting.
Point a small swamp cooler with ice at your workstation or bed for personal spot cooling.
It helps cool specific spots even if it does not cool the entire room.
- Not great for cooling down an entire room.
one person who lived it
Position light-blocking materials on the exterior of the window to prevent sunlight from hitting the glass.
This stops most heat from entering.
3 people, independently
Use portable fans to create airflow pointed at you to feel cooler in the short term.
Even a little extra airflow makes you feel cooler.
- They will break eventually.
one person who lived it
Exhaust air from an upper floor.
Hot air rises.
one person who lived it
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Cut foam board insulation, such as foil-backed polyisocyanurate or 2-inch thick foam, to fit perfectly into windows to block heat transfer.
Foam board has a fantastic R-value and blocks heat transfer more than other methods.
2 people, independently
Build a stone mantle or wall behind your wood stove to radiate heat back into the room.
Stone radiates absorbed heat back out, which can make the house warmer for longer periods.
one person who lived it
Avoid overpacking your freezer so that air flow is blocked.
Blocking air flow can cause the fan to run constantly and burn out.
one person who lived it
Open the top pane of a double-hung window when it is warmer indoors than outdoors to let hot air escape.
Hot air rises and accumulates near the ceiling.
2 people, independently
Shade windows on the sun-facing side during daylight hours to stop heat accumulation.
Blocking sunlight lowers the temperature inside your home.
4 people, independently
Leave space at the top of water containers before freezing to allow for expansion and prevent bursting.
Water expands when it freezes.
5 people, independently
Prop open the basement door and open windows on the side of the house opposite the breeze to pull cool basement air upstairs.
The outside breeze pulls the cool air from the basement up through the house.
one person who lived it
Use fans to disperse stale air or odors in rooms, such as those with diaper pails or pets.
It keeps air moving and makes the room fresher, preventing air from getting stale.
2 people, independently
Let hot leftovers sit off the stove for about 10 minutes to cool down before packing them into containers for the fridge.
This helps save energy.
one person who lived it
Pre-cool your home during cooler periods, such as at night, to build thermal mass advantage before high heat or occupancy.
Starting with a colder house reduces the workload on the AC system when external temperatures rise or internal heat loads increase.
- Effective primarily if the home is well-insulated.
2 people, independently
Reuse old soda, milk, or juice bottles filled with water as reusable ice packs for coolers.
This provides a decent amount of large ice packs that are easy to replace and fit well in coolers for day trips.
3 people, independently
Cut rolls of reflective insulation material to fit windows to block heat.
Keeps heat out better than blankets and does not make the room as dark.
2 people, independently
Set a window AC unit to low speed and place a rotating fan a few inches in front of it to push the cold air around the room.
to distribute cold air more
one person who lived it
Place a fan in a window facing outward to exhaust hot air, opening another window to draw in a breeze; if only one window exists, blow air in with the door open.
Exhausting air reduces room pressure to encourage airflow from other openings.
- If you have only one window, blow air in instead.
one person who lived it
Run window fans at night.
Helps keep mosquitoes away.
one person who lived it
Try keeping both your freezer and fridge full so they do not work as hard.
Full appliances work less hard.
one person who lived it
If you have a door-mounted ice maker during a power outage, place a container under the chute to catch melting ice.
Ice will melt and spill onto the floor if not caught.
one person who lived it
Understand that fan rotation direction mainly determines if you feel a draft, rather than how air is mixed.
Air circulation works well in either direction; the choice depends on whether you prefer a downward current or just general mixing off the ceiling.
3 people, independently
Use outside blinds for East-facing windows.
One person reported it helps a ton.
one person who lived it
Use clockwise fan rotation in rooms with high or vaulted ceilings to move warm air trapped at the top down.
2 people, independently
Set your AC to 72°F in summer and 68°F in winter if you focus on comfort over strict frugality.
Being at a comfortable temperature is considered worth the money spent.
2 people, independently
Cut fruit into small cubes and freeze them for a snack.
It provides hydration, fiber, a sweet snack, and cooling.
one person who lived it
Install a heat shield behind a wood stove to protect walls and prevent wasting heat.
It is dangerous and wastes heat without one.
one person who lived it
Freeze water bottles in an off-site freezer, such as one in a garage, to avoid dumping waste heat into the kitchen.
Refrigerators remove heat from bottles and dump it into the surrounding room.
one person who lived it
If you have easy access to water, spray your roof to use evaporative cooling.
Water evaporation subtracts heat.
- Requires easy water access.
one person who lived it
Seal windows and unused doors with tape and cover them with plastic, sheets, or blankets.
Creates a thermal barrier.
one person who lived it
Pour water on concrete surfaces like balconies and sidewalks around your house.
so they do not emit as much heat
one person who lived it
Cover windows with wire mesh screens.
Allows ventilation for fresh air without letting bugs fly in.
one person who lived it
Avoid running the central HVAC fan continuously if your ductwork is located in unconditioned spaces like attics.
Circulating air through hot or cold ducts wastes energy and increases the load on the system.
- This advice applies primarily when ducts are outside the building envelope; it may be acceptable if ducts are inside conditioned spaces like basements.
one person who lived it
Turn on a fan to generate white noise that masks conversations through thin walls.
It reduces the signal-to-noise ratio, making it harder to pick out meaningful sounds.
one person who lived it
If your home has multiple levels, position fans to push warm air out of upper windows and pull cooler air in through lower ones.
3 people, independently
Decide what you need before opening the fridge or freezer door to keep exposure time short.
Leaving the door open lets cold air escape, reducing efficiency.
3 people, independently
Install ceiling fans to help distribute cold air.
One person reported this made a significant difference in distributing cold air in their rooms.
one person who lived it
Use removable static cling film or cover windows only during peak sun hours.
This preserves airflow and keeps window spots clear.
one person who lived it
Hang wet towels on a curtain rail near windows to lower room temperature by 2-3°C via evaporation.
Evaporation lowers the temperature.
2 people, independently
Partially cover HVAC vents on lower floors to force more air upstairs, and keep upstairs doors closed to trap cool air.
One person reported this prevented freezing in one room while forcing more air to upper levels.
one person who lived it
Adjust blinds to redirect indirect light into the room.
This makes light less harsh and reduces direct heat.
one person who lived it
Set ceiling fans to rotate counter-clockwise in spring and summer.
- Turn them clockwise in winter and fall.
3 people, independently
Unplug appliances and ensure lights are off in unoccupied rooms.
to offset AC costs a little bit
one person who lived it
In humid climates, keep windows closed and use a dehumidifier instead of relying on airflow.
85 degrees dry feels better than 80 degrees humid.
one person who lived it
Set your air conditioner to your desired temperature rather than lower; turning it down further will not cool the room faster.
For most systems, the temperature setting acts as a destination for on/off cycling rather than a speed control for cooling output.
- This may not apply to mini-splits, variable flow compressors, multi-stage systems, or car AC vents.
one person who lived it
Fill empty space in the freezer with Styrofoam blocks, balloons, or air-filled bags instead of water to limit air exchange without requiring energy to cool.
These materials are reusable, do not need to be cooled down, and help prevent air changes when the door opens.
2 people, independently
Set the thermostat to the desired temperature rather than the maximum setting, as heaters have a fixed power output.
Setting it higher does not speed up heating; it only causes the heater to run longer until the higher target is reached.
one person who lived it
Use ceiling fans set to push air downward to add to personal comfort by moving air across the skin.
Fans blow away the layer of heat emitted by the body, aiding in cooling without lowering the actual room temperature.
one person who lived it
Freeze water in plastic quart containers to use as ice blocks that leak only water if damaged.
They avoid the chemical leakage associated with standard ice packs.
one person who lived it
In humid conditions, move air around with a fan to aid evaporation.
evaporation doesn't work well in humid spots
one person who lived it
Apply aluminum foil to windows using soapy water instead of strong glue for easy removal.
Foil is cheap and soapy water avoids strong glue.
one person who lived it
Draw dark curtains or blinds to block sunlight from entering through windows.
5 people, independently
Spread hot food like chili into smaller containers to increase surface area and speed up cooling before refrigeration.
Increasing surface area cools the food faster than leaving it in one large pot.
one person who lived it
If outdoor temperatures drop below freezing, leave water outside overnight to freeze instead of using the freezer.
This saves the energy required for refrigeration.
- This is region-specific; it may not work if you live in a warm climate.
3 people, independently
Cover your refrigerator or freezer with blankets or old towels during a power outage.
This improves insulation to keep the interior colder.
one person who lived it
- Keep refrigerator and freezer doors closed during a power outage.1
Use a dehumidifier to allow setting the air conditioner at a higher temperature while maintaining comfort.
Humidity control allows tolerance for higher heat and cuts electrical usage in hot areas.
2 people, independently
Crack open interior doors if windows are cracked but air is stagnant to improve circulation.
Air circulation helps prevent stagnation.
one person who lived it
Use energy-efficient lighting like LEDs instead of incandescent bulbs.
Otherwise you'll generate heat with your lighting.
one person who lived it
Consider using a small window AC instead of a standalone dehumidifier for similar power consumption, as both dehumidify but only the AC expels heat outside.
Dehumidifiers function similarly to ACs but discharge condenser heat into the room, whereas window units remove that heat outdoors.
one person who lived it
Monitor and replace HVAC filters regularly during dusty work like drywall installation to prevent damage to evaporator coils.
To prevent ruined evaporator coils from demo work.
one person who lived it
Construct a DIY evaporative cooler using a styrofoam cooler, ice, and a fan blowing upwards.
- Evaporative coolers don’t work very well in high humidity.
4 people, independently
firewood, wood7
Gather free firewood from fallen trees on crown land or your own property.
Avoid burning pine in wood stoves.
It is a sappy wood that can cause creosote buildup in the chimney.
2 people, independently
Gather free firewood from fallen trees on crown land or your own property.
3 people, independently
Place bird feeders near firewood stacks or keep a toad nearby to control insects.
Birds and toads will eat the insects in the pile.
one person who lived it
Burn only pallets marked with an HT stamp for heat treatment; avoid blue or red chemically treated pallets.
HT stamped pallets are safer to burn, while chemically marked ones are not safe.
one person who lived it
3 more on this
Burn only hardwood to reduce smoke and pollutants.
Hardwood burns slower and greatly reduces smoke; darker, thicker smoke indicates more pollutants and wasted fuel.
one person who lived it
Check local regulations and air quality bans before burning wood, especially in cities where smog may trigger restrictions due to carbon emissions.
Wood burning makes air quality worse and many municipalities have 'no wood burning' days due to pollution.
2 people, independently
If you are willing to help chop wood, ask friends in construction or tree removal for firewood.
one person who lived it
Check the pitch of the fan blades to determine airflow direction instead of relying on clockwise or counter-clockwise labels.
Blade tilt varies by manufacturer, making rotation direction alone an unreliable indicator of whether air is moving up or down.
5 people, independently
Consider that the high initial energy cost of freezing water may offset long-term savings, particularly if the freezer is rarely opened.
Crystallizing water requires more energy than cooling air or liquid water.
one person who lived it
Seek tested evidence rather than relying on intuitive reasoning for energy efficiency claims.
Intuitive reasoning ('gut science') is subjective and requires testing to resolve disagreements.
one person who lived it