How much will solar save?

The Valley of the Sun doesn’t get any better for solar energy production if you are thinking about installing solar panels on your home.  In fact, southern Arizona is the best location for solar in the nation.  APS, SRP and TEP still provide rebates for solar electricity and producing your own energy to spin your meter backwards is an attractive idea to many homeowners and businesses. But how many solar panels do you need to do so? 

Part of the equation is limited to the amount of panels you can fit on your roof, house orientation and external shading and aesthetics.  A good southern exposure is ideal for solar power, however solar panels can be west-facing or on a west-facing slope and angled towards the south.  Some homeowners want to completely zero out their energy bills for the whole year.  Other homeowners go with smaller systems to zero out just their winter energy bills and a lower summer bill.  To calculate the size of photovoltaic’s you will need to accomplish either goal you are going to need your electricity bills for the past 12 months. 

Once you have that, add all the kWh you used each month for the entire year and divide that by 1.7.  The number you get will be the total system size needed to take your annual usage down to zero (if you divide that number by 1,000, you get kW).  So let’s say after I added all the kWh’s used for the year and came up with 23,480 kWh/year (a large home).  Take 23,480 / 1.7 = 13,812 watts.  So I would need 13.8 kW’s of solar panels to completely zero out my energy bills.  Now I can go with half of that number (7 kW system) to reduce my bills by approximately half also. 

The 1.7 factor is an estimate for only a particular type and efficiency of panel, but it will give you a good idea for starters.  If you are a visual person, feel free to contact me and I can send you a spreadsheet where you can enter in your monthly kWh usage, and a nice graph will visually show you what you are spending now on energy bills, and what they would like with a 5 or 10 kW solar electricity system.

For more information visit http://www.dsireusa.org/ to find current APS/SRP or TEP rebates and federal tax incentives for going solar.  Visit APS’s website here, SRP’s website here and TEP’s website here for more tips and information.  Michael Blue Jay also has a great website and solar calculator here.  You can schedule a free site assessment on your home with Green ID to discuss possible options for solar.  For certain homes, coupling solar with efficiency upgrades will stretch your dollar spent 30-40% compared to solar alone.

What are the most common efficiency recommendations for your climate?

I started a new Facebook dicsussion on the most common recommendations for homeowners in southern Arizona. Check it out here and I look forward to learning about common climate-specific recommendations.

Solar leasing has become popular, how about leasing an electric car battery?

The average costs for electricity from APS or SRP is around $0.12 per kWh.  Imagine paying $450 per kWh for electricity.  That’s what most of today’s electric vehicle (EV) owners are paying for a battery to power their cars.  To put this into perspective, the Chevy Volt will cost owners 2 cents per mile to drive compared to the 12 cents per mile on gasoline at a price of $3.60 a gallon.  Or a trip from Phoenix to Tucson would run a measly $1.98 on electricity or almost 6 times that at $11.88 on gas.

 Shocking as the $450 per kWh may be, a decrease to $300 per kWh is considered the tipping point to mass market uptake.  An article published by webtech company, GigaOm, sites that leasing the battery is one solution to bring down the battery costs.  If you have thought about installing solar panels for your home, you’ve probably heard about solar leasing programs or PPA’s for larger solar applications, some groups are applying this concept to the electric car market.  It will be interesting to watch if and how automakers and startup companies adopt the electric vehicle lease; and also how the EV infrastructure is built-up to meet demand.

The cost-effectiveness of switching from an electric to gas water heater

Many homeowners have an old furnace system or gas water heater and want to know if it is cost-effective to switch to an electric heat pump or conventional or hybrid water heater.  By comparing the efficiencies, initial cost and lifetime of the unit you can make an informed decision as to which one is right for you.

Estimated annual energy usage will vary depending on lifestyle but this table gives a good starting point.  Take a look at the annual cost table to get an idea payback and cost-effectiveness for your switch.

Don’t forget the “kicker” factors that also must be considered – such as if you already have gas appliances.  If so, you are already paying around $30 just for having a gas line so you will not be “penalized” for adding a new line (plus $1,000 to have a new gas line tied to your home from Southwest Gas).  This would be a factor if a homeowner had all electric appliances and wanted to switch to a gas tankless water heater.

Save energy while you cook – energy saving tips in the kitchen

Kitchen appliances can account for up to 15% of your home energy usage and how you choose to cook will impact your energy bill.  By following some energy savings tips, you can reduce your bills and here's how.

There is more than one way to skin a cat:

If you took an inventory of all the appliances you use to cook with the list might look something like this: oven, stovetop, slow cooker or crockpot, microwave and toaster oven.

As you can already guess, each of these appliances uses a different amount of energy but what is not so obvious is how much energy each one uses.  When you can choose between making a baked potato in the oven or in the microwave, which one uses less energy?  How about cooking a soup or stew over the stovetop, or using the slowcooker?  Meatloaf in the oven or toaster oven?   Just like if you lived in a smaller house, it would take less time to cool the inside of the home with the same sized AC unit than if you lived in a larger house; it takes less energy to heat a smaller space than a larger one.  So what would use less energy if you could put that meatloaf in a toaster oven compared to the conventional oven?  How much less?  You would be cutting your energy use by more than half! (and reducing the temperature in the kitchen as well).

Of course, each appliance is “specialized” to cook certain foods but when you can choose, I encourage you to do so.  Below is a table showing the energy costs of various cooking methods.

Other energy saving tips in the kitchen include:

-          When using the electric stovetops it is important to match the pan size to the element size, otherwise you will be wasting almost half the heat produced from the element.-          The ideal pan also has a concave bottom to maximize the conduction in the pan.
-          A pressure cooker will also cook stovetop items faster and with less energy because the built-up pressure drops the boiling point of water thus cooking the food faster.
-          Cleaning your appliances increases their efficiency.
-          Avoid peeking into the oven while baking.
-          Double portions when using the oven to save energy on cooking.
-          Remove foil on the bottom of ovens to improve air circulation.

Update on Tax Incentives for Energy Efficiency

The 2011 tax incentive is greatly reduced compared to last year, however there are several efforts to extend residential energy efficiency credits for measures such as water heaters, heat pumps and windows that are no longer available. Green Parent Chicago gives some great resources to keep up to date on the tax credits and I've posted a 2011 federal tax credit summary for energy efficiency improvements here as well.

Phoenix Energy Audits and the Energize Phoenix Program

There is no lack of variety of housing types in the City of Phoenix.  Phoenix neighborhoods include the idyllic Arcadia District, the lively Camelback Corridor, the newly formed Lightrail Corridor and the beautiful historic district to name a few.  In addition to a great weatherization program, The City of Phoenix has developed a new Energy Efficiency program, Energize Phoenix.  The City of Phoenix is offering huge cash incentives to make your home more energy efficient.  Energize Phoenix is a large scale rebate program for residents who live along the Lightrail Corridor.  Residents receive APS-matching rebates from the City of Phoenix and for qualifying residents, a 60% Federal grant with no upper limit is available to fund efficiency upgrades like energy efficient AC units and furnaces, duct sealing, air sealing, shade screens and insulation.  If you live along the Lightrail Corridor, Energize Phoenix is making going green as easy with little upfront money, reduced utility bills and a more comfortable home.  There has never been a better time to go green

 Program Overview:

1. Have a home energy audit performed to identify the largest sources of energy waste.

2. Your Energize Phoenix approved contractor will walk you through each recommendation, its costs and offsetting rebates and cash incentives available through APS and Energize Phoenix.

3. Complete and submit the Energize Phoenix paperwork and your Energize Phoenix contractor will complete any work you requested and facilitate the rebates on your behalf.Rebate Overview:Rebates are available upon 6-8 weeks of completion of install and include the following.

- 10 free CFLs
- 2 free low flow faucet aerators
- 1 free low flow showerhead
- 1 free low flow kitchen sink aerator

- Home energy audit - discounted to $99

- Duct sealing - 75% off net costs up to $250 rebate per HVAC system from APS; matching rebates up to $250 from the City of Phoenix

- Air sealing - $250 rebate from APS; matching rebates up to $250 from the City of Phoenix

- R-38 insulation - 75% off net costs up to $250 rebate from APS; matching rebates up to $250 from the City of Phoenix

- Shade screens - $1 per sq ft rebate up to $250 from APS; matching rebates up to $250 from the City of Phoenix

- High efficiency AC units and furnaces - $175 to $525 rebate from APS; matching rebates up to $525 from the City of Phoenix


Visit Energize Phoenix's homepage and the AZ Home Performance With Energy Star for more information.