Insulation and Wind Breaks
Insulation and wind breaks( vapour barriers) are the most important start since home heating is the biggest consumer of energy. If you have an older home (+20 years) can be a very expensive especially if the home lack a vapour barrier. But personally if your home has at least a R12 walls with a vapour barrier then I would only worry about putting in 30cm of insulation in the attic (+R40ish). usually what works the best and is a blow in insulation it can be fiber glass or as i prefer cellulose based.. if you use cellulose base it is very cheap to upgrade a house with R12 ceiling will only cost you about 600- 800 dollars with rental of the blower …if your house lacks a vopour barrier then it becomes a bit more complicated. But your best route and cheapest route is to use Styrofoam on the outside of your home with with a tyvek barrier and a new layer of siding..
If your house is expose to harse winds it is advised to plant trees on th north west side of the home to temper the winds. if exposed on the south side a tree barrier is fine too but a vine coverage works just as well..
Windows
windows are a tough sell. personally unless you have the money to do it I would not worry about it. there are much cheaper routes one can use. the only time I would recommend getting new windows is if they are physically damaged or are single plate glass. If they are dual pane they are fine. you get more heat gain from a dual pane glass window then you loose. triple pane or higher glass if your are to get them they are best used on windows that get no sun ( such as north facing windows). the cheapest method to improve ones windows is to use the shrink plastic and the two sided tape .. adding this alone will improve your window R value dramatically for a simple cost of couple dollars per window
but if you hate the yearly waste I suggest using double sided tape and thick vinyl. one can usually buy them in any hardware store. it is reusable, and gives you a better R value then the shrink plastic and you usually can get 5-10 years of reuse out of them…
if your windows are fogging or icing and this is the major reason for upgrading your windows. then you have a moisture problem in your home you would be better to install air exchanger in your home., or use a dehumidifier to drop the moisture level in your house to below the dew point. which in the winter can be anywhere 20 - 60% depending on the outside temperature.. you live healthier and happier to do so..
Hotwater
Creation of hotwater is your second biggest expense next to heating your home. if you have a hot water tank you can insulate it more and put pipe insulation on the the hot and cold lines to reduce sweating and heat loss. If your hot water line coming from your tank goes straight up from your tank. I would suggest you place the thermal break. all this is a loop it goes up and then down then up again. it prevent the hotwater from migrating out of your hotwater tank.
But if you wish to save a lot of energy on your hot water needs, I suggest you get an instant water heaters. they will save you about 25%- 50% on your energy needs. In the tank style hotwater heater you loss 15- 25% of your hotwater energy to dissipation every day . which means every 5-7 days you are heating one extra tank of hot water or in one month period that equals 4-6 extra tanks of hotwater.. If one uses and instant water heater all that is gone you only make hotwater as you need it and you never run out..
Lighting
As insignificant as it sounds. can equal a lot of energy usage. if you have say 20 100watt light bulbs in your house and they are all one for an average of 5 hours per day.. that would equal 10 kwh of energy per day. energy effiecient CFL or LED that is a saving of 2/3 - 9/10ths or or a reduction to 3kwh for CFL per day or 1kwh for LED.. some will argue that changing to instant water heater or energy efficient lights will it only increase my heating needs which is true in a sence, since this extra produced heat will onlly go tworard heating in the winter, but because you use energy efficient products does not really equal an added expense it just means your furnace runs a little longer but it still equals the same total energy cost for the winter but also one must consider that it decrease your cooling needs. so if for 8 months of the years you do not need to heat then you have an absolute saving is 75% on both your lighting and hotwater needs..
Appliances
Another big saving is in the use of appliances. switching to front load water will save you 25% - 50% on your water and energy need. buying a heat pump cloths dryer will save you 50% on your cloths drying needs plus reduce your winter heating needs significantly (10- 20%). . plus they only need 110 power and no venting required.. making sure all you fridges and freezers are 10 years old or newer.. another saving of at least 50% on food storage requirements. if you have an un heated garage or an out building you can place the freezers in them. it will reduce the heat load in your house in the summertime and the cooling needs in the winter time another saving of 25% - 50%.