Power Usage and Tiny Houses

While re-reading my last post I thought I should say something about power usage and Tiny houses.

When I lived in my 800 square foot house [yea, I identify all my houses be their square footage because if I said "the house on flint" you wouldn't have a clue what I was talking about.] I was paying around $200 per month in electricity, granted I had an electric range and we baked alot, but that is just ridiculous for the amount of space that house took up. The main cost was heating and cooling the place. It was built during WWII and had almost no insulation, so we ended up diverting all the heat/cool into the bedroom and letting the rest of the house do it's own thing. We didn't have an electric heater, that was natural gas, and it cost another $80 per month. This is a good example of why you need to take your insulation seriously. Because you are going to pay for it, one way or another.

the 500 square foot apartment had better insulation and electric bills were only $40-60 per month with gas only for hot water running $12 per month. but this is utilizing many energy saving tidbits, like changing all the bulbs in your house to CFL bulbs, using fans, using energy efficient appliances etc...

Take a look around your house, what is plugged in? probably everything right? Bad idea, get a plug in watt meter and plug your "off" appliances in and watch them suck electricity right out of the wall. crazy right? You can save 5-10% just by unplugging everything, or using a power strip with an off switch.

Your lights? how many of them are incandescent bulbs? [the "normal" lightbulb] and how many are on at any given time? An incandescent bulb is anywhere from 6-10 times less efficient than a CFL or LED. I had one incandescent bulb in my house in a lamp that used more electricity than the rest of the bulbs in my house combined. Crazy huh?

What about those long tube florescent lights? on average, each of those pulls 35-45 watts, which is great when you are moving from incandescents, but you usually have two bulbs in line with each other, meaning 70-90 watts for the light, not much of an improvement anymore is it?

In a multiple bulb group like a fan, how many lights do you have plugged in? All of them right? Why? It may seem much darker when you remove them, but cutting your light power by 2/3 or 3/4 will help your eyes adjust. also after you have used just one for a few days, you wont remember the super bright lights and your single bulb will be just fine.

Your computer is next. You probably use a desktop, these are HORRIBLE with power. unless you are doing hardcore gaming or video editing, you probably don't need the power a desktop can offer, and a laptop will usually do just fine. The average desktop power supply is 200 watts, the average laptop power supply is 90 watts. Less than half.

Now if you DO decide you want to get a laptop think about what you are going to use it for. I do mostly internet and light image editing so I don't need much at all. I picked up an eMachines 1919 netbook with 2gb of ram and a 2ghz processor for $200. It's compact as all getout with a 10.5" screen and it is GREAT on power. This little baby only pulls 30 watts at the plug. Thats HALF of a conventional LIGHTBULB.

Most higher powered laptops [4gb ram, dual core processor] will pull 70-90 watts at the plug, which is still good, but I went for energy savings at the cost of performance and it's totally paying off, I love my little computer. At 30 watts, so does my electric bill.

Refrigeration: Your refrigerator is the second most power hungry device in your house in terms of usage. if you haven't read my other post, go to your fridge with bare feet, open the door. You feel that cool? that is the cool air that WAS keeping your food cool, falling out of your fridge and to your feet [heat rises, cool falls] your compressor probably kicked on too huh? That's because your refrigerator is working to maintain the set temperature of the thermostat. That uses mucho electricity, and it happens EVERY TIME you open the fridge.

One way to combat this is to convert a chest freezer to a fridge. This way, when you open the door, the cold air remains inside, because the door is on top. Doing this is easier than shopping for a cake. 

Step 1. Acquire a chest freezer, not your grandmothers chest freezer, a modern one.
Step 2. Acquire either a manual plug and play thermostat, or if you want more precise control, you can get a digital plug and play thermostat instead.



Step 3. Plug the thermostat into the wall and your freezer into the thermostat. Set it at ~40*F for optimum refrigeration.

Step 4. Slap yourself for not doing this earlier.

That's it! You've got an efficient refrigerator!


Now the biggest power hog of your house: HVAC

Heating and air conditioning are the biggest power users in your house. You can cut down on their power consumption by doing a few things:

INSULATE: The more insulation, the less heat/cool will escape meaning your unit will kick on less and use less power. Don't skimp on insulation and follow directions to the letter, if you don't you are only throwing money down the toilet.

REPLACE: Energy star rated appliances are the lowest consumption units, get one if you can, It will cost you more, but it will save you more. If not, check the energy rating and find the lowest one you can.

Now of  course it's not going to take as much energy if you are cooling a smaller space, like for example...a Tiny house? Yea, cooling a 112 square foot Tiny house is MUCH cheaper than cooling a 2500 square foot "normal" house, even if your ac is older.  Window units are usually plenty for such a small space, even if your insulation isn't triple reinforced.

FANS: Fans move air and equalize temperature in a room, if aimed at a person it can also make a person feel 10 degrees cooler, meaning you can back the thermostat off a bit and use a fan instead.
I personally like the size to airflow ratio of the honeywell tabletop fans. Depending on your tastes, there is a quieter, more energy efficient model, or a more powerful model that moves more air.

I think that's all my tips for now. I'm writing this tired and ready for bed so if it's not the clearest its probably because I suck at writing...



One last estimation before I post this:

In my Tiny house, if I use:
3x 13 watt LED or CFL lights, one on at a time
1x 30 watt laptop/netbook, on all the time [not really]
1x 35 watt fan, on most of the time
1x 12 watt phone charger with auto off timer, on when the phones are charging.
1x 1000 watt ac or a heater unit on 2 hours per day [2 hours running]
1x100 watt chest fridge, on [cycling] 2 hours total per day
1x 1000 watt convection microwave, on 30 minutes per day

You get just over 4kwh per day at 10 cents per kwh, that's 40 cents per day, or $12.40 per month. This is pretty decent on it's own, but I usually don't use the ac and use fans and windows instead. so that would cut power use in half, making it $6.20 per month in electricity. I pay more a month for trash pickup! On a related note, the average house uses 40kwh per day, 10x more. Now you could bring these numbers down of course, unplugging your laptop and using the battery would cut  usage by 1/3, not overcooking in the microwave could save another 1/3. Better insulation would make the ac kick on less, bringing cost down.
and a solar array on the roof charging a battery bank very much could power the entire house needs, making the power charge....zero....