svetz
Works in theory! Practice? That's something else
Whether you're you're off-grid and living by the watt or just interested in reducing your carbon footprint there are some resources and ideas that you can take advantage of.
Shopping by the Watt
When it comes time to replace something, shopping by the power consumption is something that could be a major consideration.
Not all devices have Energy guides. The next best source is the Energy Star rating. For example in https://www.energystar.gov/most-efficient/me-certified-ceiling-fans/results we can see a MonteCarlo fan is 431 CFM/W and a Hampton Bay fan is 213 CFM/W. So MonteCarlo, right? Not so fast... if you look at the details at low-speed the MonteCarlo uses 6.9 W whereas the Hampton Bay uses 2.8W; so at low speeds the Hampton Bay is actually more efficient. So it depends on the facts and your usage.
There may also by other things to note from the Energy Star data. For example, both of the fans in the example above consume power even when they're off as they listen for the remote control.
DC Vs. AC
Often overlooked, inverters typically have 4% to 20% energy conversion losses, many devices like well pumps, can be run on DC directly for less watts than their AC counterparts with inverter losses.
Existing Devices
When building your Energy Audit, it is often important to know how many watts existing devices consumer. Home energy meters are invaluable for this. The most common pitfall to using them is to not leave them plugged in long enough, for example refrigerators typically consume a lot more power during the defrost cycle, but that cycle doesn't run for very long.
Home monitoring can get quite sophisticated, for example the Emporia will measure consumption from your electrical panel 24x7. The benefit to a system like this is you can see at a glance what's consuming power and any jumps in power (e.g., an LED light bulb got replaced with a power hungry incandescent).
Warning: As with all FAQ threads, posts here will be heavily moderated to keep the topic on-track and concise to make it easier for readers. That said, please share your best energy saving ideas!
Shopping by the Watt
When it comes time to replace something, shopping by the power consumption is something that could be a major consideration.
So, how do you find and compare products? Big appliances like TVs or Hot water tanks will typically have an Energy Guide tag as shown to the right. The numbers shown are averages, actual costs depend on your usage and cost of electricity. But they're still fairly good for comparing products. Let's say you're looking at $200 Toshiba TV with a $30 energy operating cost and a $250 Magnovox with a $23 annual energy cost. At the $50 difference, the Magnovox would pay for the difference in $50/(30-23) = 7 years and then be saving you money, so the Magnovox is actually the better deal. Devices that are cheap upfront often consume more power. Many times a more expensive quality device will not only serve you better, but be cheaper in the long run. Energy Guides numbers are based on average usage, so YMMV, they're best uses as a comparison guide. |
(click the image to make it bigger) |
Not all devices have Energy guides. The next best source is the Energy Star rating. For example in https://www.energystar.gov/most-efficient/me-certified-ceiling-fans/results we can see a MonteCarlo fan is 431 CFM/W and a Hampton Bay fan is 213 CFM/W. So MonteCarlo, right? Not so fast... if you look at the details at low-speed the MonteCarlo uses 6.9 W whereas the Hampton Bay uses 2.8W; so at low speeds the Hampton Bay is actually more efficient. So it depends on the facts and your usage.
There may also by other things to note from the Energy Star data. For example, both of the fans in the example above consume power even when they're off as they listen for the remote control.
Tip: Don't like the standby power needs? Install a switch to cut it's power. For example, many TVs consume 30 or 40 watts in stand-by mode, those can be plugged into a power-strip with an on/off switch.
DC Vs. AC
Often overlooked, inverters typically have 4% to 20% energy conversion losses, many devices like well pumps, can be run on DC directly for less watts than their AC counterparts with inverter losses.
Existing Devices
When building your Energy Audit, it is often important to know how many watts existing devices consumer. Home energy meters are invaluable for this. The most common pitfall to using them is to not leave them plugged in long enough, for example refrigerators typically consume a lot more power during the defrost cycle, but that cycle doesn't run for very long.
Home monitoring can get quite sophisticated, for example the Emporia will measure consumption from your electrical panel 24x7. The benefit to a system like this is you can see at a glance what's consuming power and any jumps in power (e.g., an LED light bulb got replaced with a power hungry incandescent).
Warning: As with all FAQ threads, posts here will be heavily moderated to keep the topic on-track and concise to make it easier for readers. That said, please share your best energy saving ideas!
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