Powering Down: Toward a 90 kWh month

Powering Down
Toward a 90 kWh month

Who are we?
Will Emigh – number cruncher, analyst
Maggie Sullivan – mastermind, implementer
Greencouple.com

SIREN contest
Southern Indiana Renewable Energy Network
Reduce 2010 usage compared to 2009
We already did a lot in 2009; could we do more?
Terminology: kW vs. Watt, kW vs. kWh

2009 vs. 2010

Our goal: 90 kWh a month
For the environment, what matters is how much electricity you use
For comparison, it’s useful to look at usage per square foot

How much is 3 kWh?
2 60-Watt bulbs on for a day
A 20 year-old refrigerator in a day
One load of clothes in the dryer
A desktop computer and monitor on for a day

How does that compare?
Based on average annual usage
Adjusted to our home size

Pop quiz!
How much electricity do these items use?
CFL
Laptop
Space heater
Dishwasher
Clothes dryer

Correct answer: how would I know?
People overestimate low-usage items and underestimate high-usage items
Unless it’s Energy Star, you probably can’t tell in the store
A Kill-A-Watt can tell you for plug-in items

actual answers
“Public perceptions of energy consumption and savings” by Attari, DeKay, Davidson, de Bruin

actual answers
How much electricity do these items use?
CFL 12 Wh
Laptop 30 Wh
Space heater 900 Wh
Dishwasher 1200 Wh
Clothes dryer 6000 Wh

Too many cooks
There’s lots of advice out there
Not all of it applies to our climate, home, or lifestyle
Our rules:
Track usage
Try new things
Measure specifically when possible

How might we differ from you?
1350 sq ft house
Gas heat & stove (although furnace still uses a lot of power for the fan)
Work from home
No kids (but a dog)
No dishwasher
Good house orientation (windows across from each other, south-facing windows, etc.)

Tracking (over 200 measurements)

Tracking
I mark down current measurement, time, and comments every day after work
Can buy real-time monitors, but they tend to be expensive
Working with Ted Mendoza of Gengee to create an iPhone app to make it easier

Measuring
Can’t tell what to focus on when you don’t know what’s working
Kill-A-Watt works for normal outlets
Larger items (water heater, furnace) can be estimated through tracking
We turned off our water heater while on vacation to see how the base load changed

Heating/coolingare the biggest culprits
Freezer
Refrigerator
Hot tub/pool heater
A/C
Furnace
Water heater
Dryer
Stove/Oven

Pre-challenge, what did we do?
No impact on our quality of life
No major expenses
No major effort

Low-power setting on laptops
Desktop with monitor can draw 150 Watts
Laptop draws 30 Watts
Netbook draws 15 Watts
Hibernation is less than 1 Watt
Suspend uses effectively no energy
Over 2 kWh per day for desktop on continuously
Our average laptop usage: < 0.5 kWh

Power strips for almost everything
TV
Wii
DVD player
Toaster oven
Stereo
Cable box
Anything with a clock or a remote

Lighting: CFLs
Cheap (often free through deals – check with your utility company)
20% electrical usage compared to incandescents
Produce less waste heat
Reduced bulbs in fixtures (don’t need 4 bulbs in the bathroom at night)

high in the summer,low in the winter
Set thermostat to 78 in summer (75 during the hour we’re trying to get to sleep)
Set thermostat to 65 in winter (60 while asleep)
Check utility company for deals on programmable thermostats

Post-challenge, what did we do?
Made sacrifices
Didn’t worry about whether we could maintain long-term
Spent more money
Tried more things
Cut out tiny things just because we could
Charged laptop during business meetings
Stayed in the same room to reduce light use

New refrigerator
Old one (17 years) drew 2.6 kWh a day!
New Energy Star unit of same size uses 0.6 kWh a day
Cost $700 minus some rebates (check with your utility company)
Will pay for itself in about 10 years (less if rates go up)

No A/C
Closed windows and blinds during the day, opened at night
Fans set up to encourage air replacement at night and ceiling fan
Cool water in fridge; ice pops in freezer
Occasional escapes to A/C (movie theater, etc.)
Got up to 82 in the house (prior to heat wave in July/August)

No dryer (line drying)
Our dryer uses 4-6 kWh per load!
No such thing as Energy Star dryer
Set up drying rack for underwear/socks
Used two lines that got good afternoon sun to dry everything else

Camp shower (Whoa!)
Our water heater uses about 1-2 kWh to reheat
We tried cold showers, but it was too cold!
Purchased a kit at Dick’s Sporting Goods
Black 5-gallon bag with spigot
Plastic privacy barriers that hang from a tree
Put a welcome mat underneath to keep feet cleaner
Put bag in the sun in the morning
Sometimes took bag inside to use, but it was unwieldy

Solar cooking
Didn’t actually help much, since our stove is gas (but an electric stove draws 2.4 kW!)
Sometimes replaced slow cooker use, which is about 600 Wh for ours
Fun to put rice out in the morning and eat it at night

small solar charger for phones
Take forever to charge
Phones (even smart phones) don’t draw much power
Not worth it unless camping or traveling

To infinity and beyond!
On-demand water heater
More efficient washer/dryer
Solar water heater
PV panels
Light-colored metal roof
Attic fan

Solar furnace!
Our winter electrical use is 1.5-2x summer
Furnace fan
Harder to heat water
Solar furnace fan uses 90 Watts
Produces hot air continuously on sunny days
Come visit on Sunday!

We did it!

Not sustainable
We like taking showers in the morning
Line drying isn’t always convenient
Raining
Too many clothes
Can’t be around to put them out/bring them in
Sometimes it gets really hot!
Winter!

Still, We’re doing well

Remember this?

What do we recommend?
Focus on things that are on a lot
Focus on things that draw a lot of power
Check out new technology
Energy Star refrigerators
Solar furnace/water heater/panel
Don’t worry too much about curtailment

Replace incandescent with CFLs
No reason not to at this point
Probably won’t save a lot, but the return on investment is high

Hibernate/Suspend computers
Leaving a desktop on is worse than leaving a light on
Leaving a laptop on is worse than leaving a CFL on
Easy to change power settings
Easy to hibernate/suspend when not in use

Replace old appliances
Refrigerator
Greatest change in efficiency in the last 10 years
Water heater
Clothes dryer
Washing machine
Efficient ones cut down on dryer time as well

Remove extraneous heaters/coolers
A fridge in the garage
A chest freezer
Even a tiny dorm fridge uses almost as much as a normal one!

Solar water heating
Makeshift (camp shower)
Cheap
Easy to setup
Professional
Can shower in the morning
Easier to shower inside

Line dry as much as possible
Clothes dryers are TERRIBLE
Line dry in the summer
Line dry in the winter
If you have to use a clothes dryer
Make sure your washer is spinning most of the water out
Vent heated air into the home in winter

How much are we talking?

Questions?
www.greencouple.com

Powering Down: Toward a 90 kWh month

by greencouple on Oct 30, 2010

Accessibility

Categories

Tags

Upload Details

Usage Rights

2 Embeds 201

Statistics

Powering Down: Toward a 90 kWh month — Presentation Transcript

http://greencouple.com	200
http://translate.googleusercontent.com	1