diy solar

diy solar

Minimizing Consumption

svetz

Works in theory! Practice? That's something else
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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.

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.
0072-energy-guide-label.jpg

(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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Replacing a dirty, clogged air filter with a clean one can lower your air conditioner’s energy consumption by 5-15 percent.

In summer, a breeze (e.g., a ceiling fan) allows you to raise the thermostat setting about 4 degrees without impacting your comfort (YMMV).

10 tips to reduce water heater costs: https://happyhiller.com/blog/water-heater-tips-save-money-energy/
Also during the winter time set the ceiling fan to reverse and it circulates the warm air at the ceiling. This really works well in the kitchen during the late fall, winter and early spring. Helps to circulate warm moist air into the dinning room and living room of our house. When we are done baking (oven off) we leave the oven door open and let the heat escape into the house.

Figure out what you use, really need and what you don't - unplug things that are not in use.

Change all lights to LED bulbs. Same with TVs and computer monitors.
 
I’ve set up a lot of off grid systems. Almost invariably it’s cheaper to upgrade your power system than buy ultra energy efficient appliances.
Same goes for passivhaus type buildings, nice but a lot more expensive than upgrading your power system and using airconditioning to achieve your desired climate.
 
Back when I lived in Colorado the winters were cold and brutally dry. Was really excited to find an air-diverter for the drier that would put the waste heat/moisture into the house. (Not to mention where it exhausted to would become a very ice walk-way).
 
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Hi,
Thanks for the tip about “Home energy meters”!
Your link let me to discover what appears to be a nice “Open Source” monitor, I’m going to try one of these:
IoTaWatt

 
All of my appliances & Devices are now Energy Star+ efficient rated now. By updating everything over the past couple of years, starting to just before I moved into my off-grid home, I cut 1/3rd off my daily power usage and THAT adds up to big bucks !

My Offgrid home designed and built by myself is hyper-efficient does not "need" AC in summer as it never gets above 26°C/89°F inside even during a heatwave of 40°C/104°F. The Radiant Heating system runs a total of 5 hours in 24 hours when it is -30°C/-22°F outside and that is without supplemental heating from wood stove or other, while keeping whole house temps at 24°C. WHAT Heating system does that ? It depends on the house it is heating and how well it is insulated. Insulation & proper updates to energy efficiency are worth their weight in gold, especially when it comes to daily liveability & comfort.

Efficiency starts with the greatest waster of energy, which is the Structure itself. Heating & Cooling are the two heaviest, followed by the Big Appliances.
 
@toms menitioning Passivhaus reminded me that "air leaks" are probably the biggest energy losses in winter and summer after insulation. A few cans of expanding styrofoam and caulk to seal up those leaks is probably money well spent. See this link for more.
 
A key component for having a more air-tight home that is liveable, comfortable & "Healthy" is to have a proper Air-Exchanger system in place, most especially when the home is sealed up like in Winter. Heat Recovering Air-Exchangers work very well and they do recover outgoing heat and prewarm the incoming fresh colder air. These units can be inexpensive to outrageously expensive & complicated. They have to be properly sized to the home and the amount of cubic feet of air that has to be exchanged within a 1 hour period.

There are several DIY Options that are available, some work ok, some work really well and others are a waste of effort.
There are MANY Commercial versions & variations, several which can be serious Power Hogs as well. Some have Humidifiers and even dehumidifiers as they can be used in multi-climate applications.

My own HRV is a DIY based system which I customized a little for my application, it only uses 12V@0.35A while running. It cost me less that $200 to build and while not super-duper efficient it does make a huge difference in both summer & winter because it is also setup to act as a power flow vent in summer to pull warmer air out of the home.
 
The "entertainment" center has the TV, DVD and some other stuff that all consume stand-by power. It's only used once a week or so. I leave the other TVs (e.g., guest bedroom) unplugged since they nearly never go on and unplugged is the ultimate in lightening protection.

I could use a smart strip, but typically you use the TV to activate a smart strip. My TV uses 68W when running, and 36W in standby.
At 13¢ per kWh, that's 36 x 24 x 365 / 1000 * 0.13 = $41/yr.

By using a mini smart socket (.2W) and Alexa "Routine", that goes down to .2 x 24 x 365 / 1000 * 0.13 = $0.23/yr.
But... it takes so long for the 3W fire stick to boot up I typically leave it plugged in, so +$3.50 ?
 
a few Tips I have employed but may not be practical for everyone.
I have one 120V outlet that runs my Satellite Modem & Router, that equipment is on a Switched Plug. OFF when not in use / required.
My Radiant Heating system, controller, relays, circulation pump & related are also on a Switched Plug. OFF during non-heating season.

I have Two Power bars: Can save you lots of power when things that are not needed can be turned off.
1) runs the TV Set and HP Elite Desk NUC i7 Computer, and Raspbery Pi4 (solar control system)
2) Run the "Wall Warts" for Cell phone, wireless headset etc...
* All switched OFF when not needed.

BTW: Raspberry Pi Computer have come a Long Way over the past few years. They are more than capable of streaming & playing video up to 4K, running OpenOffice/LibreOffice and so much more. 12V/4A to run one. Couple that with a respectable LED TV Screen like I have done and you can enjoy everything without feeding the Power Goblins.
 
DON'T TRUST THOSE Energy Guide labels as "absolute" planning numbers, they're averages. Understand your costs of electricity. What it will take to make or buy the power. In NH, on the grid, the dealers were selling on those "average" annual costs, assuming xxx per KWH of electricity. I looked at my grid charges and figured they needed to extend that sticker half the way around the water heater to equal NH electricity costs. Read up and prototype some engineering numbers. Maybe you want to solar preheat the water and move your showers to the evenings. Maybe you want to go grocery shopping in the mornings to allow solar to freeze the meats during the day? Understand when the power is there, and when it's best to use it.
 
Hot Water Tanks are Notorious energy consumption devices.
The Energy Saver blankets or Jackets do make a significant difference, even with the highest efficiency models. NOTE there are different ones depending on fuel being used, Electric, LPG or Natural Gas.
You can also install timers so they're not cycling for periods you're not around or for when you'll have excess solar energy.
 
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Whole house fan & Swamp Coolers
When I lived in Colorado we didn't have air conditioning. With the arid conditions it would often be cool at night and not hit 99° until late in the day. The house would heat up of course, but we generally worked to 6ish, and by then it would have started cooling off. The whole house fan sucked the heat of the house and pushed it up into the attic, cooling the attic off too.

Even then, there were a few days were is stayed hot until 9ish. For those days we deployed the swamp cooler box fan. It was cheap little thing (box fan with a small sump that dripped onto an evaporative pad. With the whole house fan we didn't have to worry about humidity build up.
 
I could use a smart strip, but typically you use the TV to activate a smart strip. My TV uses 68W when running, and 36W in standby.
At 13¢ per kWh, that's 36 x 24 x 365 / 1000 * 0.13 = $41/yr.

From a battery saving standpoint, depending on your tv / monitor, try reducing the brightness. Or better yet, reduce the backlight if you have one.

The power draw while in use can be cut pretty drastically, nearly half of the rated draw at times. Ideally you are watching at night, but if watching it in daytime, try to shade the monitor as much as possible so you can lower the brightness / backlight. Do backlight first, as it is more effective than brightness.

Crank the backlight waaay down until you just can't stand it any more and bring it back up a hair. See if you can get used to it, because turning it way down can seem jarring at first. In my case, I was able to leave the backlight turned way down when watching re-runs of Star Trek which are already memorized. :) For stuff that's important, turn the backlight back up.

Aside from entertainment, this trick can come in real handy if one is in an emergency weather situation which must be monitored for long periods, and you want to save as much battery power as possible.
 
As far as TV's go. You can reduce the watts they use by lowering the Backlight setting.

I have a 50" (5yr old / not a smart TV). Smart TV's use more power.

The Backlight can be set from 0-20.

At 20 it uses 57.1 watts.
15 - 47.9 watts
10 - 38.8 watts
8 - 35.1 watts
6 - 31.5 watts
5 or below - 29.5 watts

I've been trying to find a good used 40" non-smart TV to test. I'd gladly buy a new one, but they all use more power.
 

Install a Mailbox​

One of the sneakiest energy loss places is a mail slot. Many older homes, still have a slot for the mailman on the front door. Unfortunately, it’s also letting a considerable amount of air out of your home. The easiest fix is to fill the slot with a car-wash sponge to block it off.

Freeze The House​

Have a TOU, excess solar, and hot weather? During the day while you're gone set the AC to be colder while there is excess solar power and go to normal either before the TOU rate change or you get home. That way the house can thermally coast through the higher TOU rate and not use up precious battery during the TOU rates.

Tame the Sun​

Have a large east/west facing window the room(s) get hot? Window films can reflect a lot of that IR keeping your home cooler.

Plant a Tree​

Shade tree that is. Trees that drop their leaves are great as they provide shade in summer and light in winter, so better than window films!

Ditch the Desktop​

Instead of getting a desktop computer, invest your money into a laptop. It will be more convenient and energy-efficient.

Vacuum your refrigerator coils​

This tip wins the prize for being the least exciting, but it’ll help your fridge release heat more efficiently.

Garden or path Lighting​

Paint rocks in your backyard with glow-in-the-dark paint. Now they absorb sunlight during the day and give their garden a soft light through the evening.

Swap that BBQ for a solar oven​

With solar ovens you don't have to wait for the coals to get hot, or clean up messy ash/soot. You don't have to get propane tanks refilled.

Take the GoSun Stove, for example. It has the BTUs to cook six hot dogs in about ten minutes, even on a cloudy day. ref
Watched a YouTube video on these, they look impressive, but it's more like baking than charing.
solar-oven-gosun.jpg
 
Back when I lived in Colorado the winters were cold and brutally dry. Was really excited to find an air-diverter for the drier that would put the waste heat/moisture into the house. (Not to mention where it exhausted to would become a very ice walk-way).
Maybe not one for the California crowd, but this is one of my favorite "free energy" hacks. It's a huge amount of warm, humid air that would otherwise just go out the window.
 
Whole house fan & Swamp Coolers
When I lived in Colorado we didn't have air conditioning. With the arid conditions it would often be cool at night and not hit 99° until late in the day. The house would heat up of course, but we generally worked to 6ish, and by then it would have started cooling off. The whole house fan sucked the heat of the house and pushed it up into the attic, cooling the attic off too.

Even then, there were a few days were is stayed hot until 9ish. For those days we deployed the swamp cooler box fan. It was cheap little thing (box fan with a small sump that dripped onto an evaporative pad. With the whole house fan we didn't have to worry about humidity build up.

I wholeheartedly endorse the Whole House Fan. Here in the SF Bay area, it is rare that it stays warm at night. With the whole house fan, we close up in the morning and it stays cool till late in the afternoon. We can usually just use the whole house fan to cool off in the late afternoon. It amazes me that Whole House fans are not more popular here. They are huge energy savers.
 
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