Home Energy Seminary
1. Introduction: Climate Change
2. Home Energy: Lights
3. Appliances:
• Fridges, Washing machines, AC
4. A little Physics: Understanding your home!
• Building diagnostics
• Insulation vs. Air-tightness
5. Windows
6. Heating Systems
Cumulative CO2 Emissions from 1800-1988:
The Ecological Debt of the North
Graph by Martin Storksdiek
“As the global climate changes, extreme weather events such as droughts, floods, heat waves, heavy rainfall, tropical storms and hurricanes are expected to increase.”
(Dr. David Easterling, National Climatic Data Center, 9-26-00)
Flooding of the Ohio river (NOAA Photo Library; www.photolib.noaa.gov)
Temperature rise of 1 degree Celsius from the end of the twentieth century will leave up to 30 percent of species at risk of extinction. (IPCC, FAR)
Drought Popenguine, Senegal (United Nations Photo Library
www.un.org/av/photo)
Climate Change & Extreme Drought
Severe drought as a result of global warming threatens to spread across half the Earth's land surface by 2100, turning one third of the planet into a desert.
(Hadley Centre for Climate Prediction and Research, 2006)
Average Bangladeshi produces 0.2 tons of CO2 Average American produces 21 tons of CO2
Millions of Bangladeshi will loose their home and livelihood due to sea level rise.
Climate Change & Equity
The Solutions to Climate Change can address many
other problems:
Energy SecurityNational Security
Job SecurityLocal Air Pollution
EfficiencyAn estimated 94% of
materials become waste before a product is even
manufactured.
Only 6 per cent of materials extracted each year are
embodied in durable goods!
Home Energy Seminary
Save Money! Protect the Climate!
Americans spend more than $160 billion a year to heat, cool, light and live in our homes.
Homes use about 21% of the energy we use as a nation. Homes contribute about 17% of our national emissions of
greenhouse gases.
Switch To Compact Fluorescent Light bulbs (CFLs)! More expensive upfront ($1-$12)
but they'll save $30-$50!
Many different types of CFLs available (including for small fixtures, 3-ways, etc).
Last 10 times longer!
Watch for available rebates.
Compact fluorescent bulbs• Take 1-2 min to reach fullest brightness
• Are less bright when it is cold• If you are concerned about brightness, buy a brighter one!• Should not flicker after 1-2 seconds
• Are not all of equally good quality • Test out a brand before you invest in a lot of them
Compact fluorescent bulbs
Compact Fluorescent Bulbs:• Regular CFLs don’t work in dimmable
fixtures
• Buy a dimmable CFL
• Check out www.efi.org for other specialty bulbs
• Have a small amount of mercury: call your city about disposal. (But they still use less mercury than would have been produced at the power plant when you use a regular incandescent bulb)
Compact fluorescent bulbs
If every household in the US replaced 5 fixtures with CFLs:
Savings: 800 billion kWh
The equivalent of shutting down 21 power plants.
Compact fluorescent bulbFacts!
Halogen Torchieres Nice light but…Energy Hog!
Uses 300W – 500W….
(a normal bulb uses 60W)
Halogen torchieres are also a fire hazard!
Buy a torchiere with CFL!
Appliances:
Energy Star: www.energystar.govLook for the energy star label! More than 35 product categories are available with the ENERGY STAR label.
Careful! Energy Star appliances are rated by size class.
Look for the smallest appliance that fits your needs.
RefrigeratorIf your refrigerator is more than 8 years old, it makes sense to replace it. The new one will pay for itself in energy savings in about 3-6 years.
Again! Energy Star appliances are rated by size class.
Look for the smallest refrigerator that fits your needs! Side-by-side are least efficient.
BAD: Top-loader GOOD: Front-loader
Washing Machines
40 to 60% less water 30 to 50% less energy 50 to 70% less detergent
Top-loader: 40 gallons of water per load. Front loader: 20 - 25 gallons. You could save as much as 7,000 gallons of water per year!
Gentler on clothes.Decreases drying time considerably.Do a better job cleaning clothes. Be modern, get a front-loader! Top-loaders are the technology your grand-parents used!!!P.S. Only do full loads. Use cold water as often as possible.
Front –loading Washing Machines
Conventional Dryer
• 800-1000 kW/year
•$80-$120/ year
Be old-fashioned - dry your clothes like your grand-parents did!
Tip: If you do not have time to hang all your clothes, hang the heavy, and thick items: towels, sheets, socks…
Use Fans Instead of AC!
Only 10-15% of the energy an AC uses.
(Shut the fan off when you leave the room, because it does not actually cool the air but just move it. The exception to this is a window fan to get cool night air from the outside into the house.)
Be cheap! Turn it off!Most electricity is used by things that are on a lot and use a lot of power:
Refrigerator (500kWh-1300 kWh per year)
Freezer (500kWh-1300 kWh per year)
Desktop Computer (300-1000 kWh per year)
Lights
Don’t forget to turn your heat or AC off /down!
Great Myths
Turning off your computer
will harm it.WRONG!This used to be true back when computers had green screens
and punch cards……
Great Myths
Leaving your heat on is more efficient than turning it down because you need so much
energy to heat the house back up.
WRONG!Think about it!
It’s as if you’d claim that putting down your suitcase while waiting for the bus uses more energy than holding it up the
whole time, because you’d have to pick it up again.
Get an Energy Audit
A professional will be able to analyze your house and give you advise.
You’ll get most out of it, if you are well educated!
Prepare well and ask lot’s of questions!
Convection
The flow of hot and cold gases
This is how heat travels through leaks, cracks and gaps in your house.
A Little Physics:
How Heat Travels:
Will she be warm enough in the winter?Convection:
Air leaks:This is why you wear a wind breaker
over your woolen sweater!
Where is the Energy Going?Ceiling
4%
Doors1%Windows
13%
Floor10%
Equip. Efficiency
16%
Infiltration34%
Walls22%
What You Can Do:Use weather stripping and caulking!
It’s cheap, it works!
Stay warm!Save Money!Protect the Climate!
From the simple to the sophisticated, air sealing pays!
Heat exchange between adjacent molecules
Conduction
This is how heat travels through materials.
Some materials conduct heat better than others.
Insulation slows the movement of heat.
Conduction
Insulation:This is why you wear a
woolen sweater in winter and a cotton sweatshirt in the summer!
Windows are rated by: Conductance: U-value
Low U-value = high insulation properties
You want: Low U- Value
Insulation is rated by:
Resistance: R-ValueHigh R-value = high insulation properties
You want: High R- Value
How Conduction is measured:
Insulation (conduction):
Get your walls and attic insulated!
Insulating your walls and attic, along with addressing leaks around your doors and windows, can save as much as 30% on your heating bill.
Insulate before you replace windows: it will cost you much less and save you more.
Watch out for active knob-and-tube wiring before you insulate!
Fiberglass vs. CelluloseFiberglass: like a woolen sweater+ easy to install+ can be cheaper + moisture tolerant- does not stop air flow- poor fire protection- most of the times poorly installed
Cellulose: like a down jacket+ stops air flow+ better fire protection+ can fill up nooks and crannies.- does not tolerate moisture very well
Cellulose Installation
This should be the very first home improvement you do!
Pay back is 1-5 years Cost: $1000 - $5000
General Insulation Strategies
Use an insulation that air-seals and insulates– Spray foam– Dense-pack (or wet-spray) cellulose
When practical, insulate the outermost plane– Attic roof rather than floor joists– Crawlspace floor and walls rather than ceiling– Basement walls rather than ceiling
Slide by Paul Eldrenkamp @ Byggmeister
RadiationElectro-magnetic waves emitted from hot objects
This is the how the sun heats the surface of the earth. This is why it can get very hot in a car in the summer.
Window Replacement
+ New high-quality windows are definitively more energy-efficient and will cut your heating bills.
+ You’ll get rid of lead paint.
+ New windows are easier to operate and clean.
- High-quality windows are expensive ($300-$600 per opening)
- They have a very long pay back (30-50 years)
- Esthetics
Window Replacement
The Don’t’s• Don’t get single pane.• Don’t be lured by the cheap price of some windows. You really get what you pay for.
The Do’s• Get double or triple pane windows. • Get high quality windows.• Make sure to get an experienced installer who will pay attention to details (and insulate the weight box)• Get Low-e coating with argon fill. • Wood or fiberglass frames are best.
Largest energy expense in the home.
What system? Steam, hot water, forced air?
Gas, oil, electric, wood
Heating Systems
Sizing?
Most systems are oversized
To tell how much, see how long it runs out of each hour during cold weather.
If less than half the time, a smaller system will save energy.
Replacing your system:
Insist on a heat loss analysis
(ACCA Manual J)
If your plumber sizes the system by the old system,take your business elsewhere!
Efficiency
Check www.energystar.gov
Go for over 90% efficiency. (Gas boilers can achieve higher efficiencies.)
Check for rebates!
Don’t trust just your plumber! A little upfront research can make a
big difference.
Get this book, it will change your life:www.aceee.org/consumerguide/index.htm
Replacing a Heating System
Stay away form electric heat.
It’s very expensive!!!!
No electric water heaterNo electric furnacesNo space heaters
Electric Heat
Exception: If you want to heat only a small space in a large house
#2 Heating Oil
1/3 more carbon emissions than natural gas
Natural Gas
More climate friendly!
More chimney friendly!
Less air pollution!
No oil tank!
More expensive than oil….
Oil or Gas?
… unfortunately, doing the right thing is not always the cheaper thing…
Also:
Efficiency can make up for it.
No oil tanks, no hazards…
Saving energy in your home does more than just save money!
It’s a step towards securing the future for our children!
Thank You!
High-cost but low-impact issues
Vapor barriers– Vapor diffusion not a big problem in our
climate– Big difference between a vapor barrier and
an air barrier – Vapor barrier paints
Slide by Paul Eldrenkamp @ Byggmeister
High-cost but low-impact issues
Roof venting– Cold roof vs. hot roof (vented vs. unvented)– Instead of investing heavily in venting,
invest in better roof insulation
Slide by Paul Eldrenkamp @ Byggmeister