Living in my green home bubble at Mueller Austin, I sometimes forget that other Texans don’t always enjoy the same low utility bills that I do. This became apparent on Friday when a prospective buyer asked me how much my electricity bill was after seeing the solar panels on my rooftop, and it got me to thinking about how we share utility usage information and how useful that actually is.
How much are your utility bills? It’s a reasonable question, though there are always challenges when you ask about utility bills as lifestyle and behavior play a big part of resource usage:
- How many people are there in your home?
- How many people work at home / spend all day at home?
- How cold do you like your home, and do you open the windows?
- Do you have pets that require you to open the doors all the time?
- Do you consciously conserve energy and water, or do you have systems that do?
Beyond that, there are amenities and other factors which impact your utility usage in a green home:
- How energy efficient is your home?
- How big is your home and what are the elevations and sun exposures?
- How energy efficient and on what resources do your appliances run?
- Do you have a large yard with thirsty plants or water feature?
- Do you harvest rainwater or solar power?
That aside, I answered the question with a few caveats about my lifestyle – a family of four with two children under five and a dog, an almost allergic reaction to excessive heat on my part which leaves the summer thermostat around 73 degrees, and a general desire to keep windows closed all year round to keep out allergens.
In terms of my house, the key amenities in my opinion can be described by saying I have electric cooking equipment and dryer, and a gas furnace. My 1422sqft home was rated as three stars in Austin Energy’s Green Building Program in 2007, and we don’t have any grass remaining in our yard so the sprinklers have been off for years. We have a 3kW solar array on the roof, and don’t harvest rain water.
Unfortunately, producing useful utility bills using Austin Energy’s online service is not straightforward for solar PV panel operators like me. The way in which solar production is allocated against electricity usage has recently changed, so Austin Energy have recently issued new account numbers to folk like me. As you can see from the Mueller Megawatt site, there are over 210 domestic solar power plants in Mueller already, so I’m not alone in my challenge of providing useful information at the click of a mouse. I had to dig out my spreadsheet of monthly bills and check my solar production to ascertain our generation and usage which is as follows:
Solar production averages 12.5 kWh/day over the last 1319 days. With Austin Energy’s new sunshine pricing schedule, given that our house doesn’t produce more power than it uses, that equates to $585 per year.
Our utility bills are an average of $24 per month for gas, and the chart above shows the total utility bill including gas. In addition, I show a split of the bills in February 2013 – a low month for electricity usage as we aren’t using the HVAC.
What does this all mean? We have a number of fixed charges, and then something to offset our summer HVAC usage. While house buyers often ask to see this type of thing, it doesn’t really offer any guarantees as my usage and lifestyle patterns might vary to yours.
Are there any antidotes to this generic type of usage data being extrapolating into someone else’s lifestyle?
I think the David Weekley participation in the Environments For Living (EFL) certification program is one example of a step in the right direction. ENERGY STAR is pretty handy too, but if I had the choice I’d choose EFL, and here’s why:
EFL guarantees your home energy usage for heating and cooling. The builder submits home design plans for review, and then the homes are tested against the design. After that, the buyer has a guarantee of the maximum energy usage to heat or cool the home (in addition to guaranteeing the comfort levels in the home with respect to temperature differential between rooms).
So instead of me saying, “we use around $50 of electricity to cool our home in summer but we let our incontinent geriatric dog out every 30 minutes”, an EFL home buyer gets a guarantee of energy usage to heat or cool their home no matter what their lifestyle. The only variable then for electricity usage is the cost per unit – which unless you have a whole bunch of solar panels, is out of your control.
To find out more about buying homes at Mueller and beyond, call 512 215 4785