Our electric bills over the past couple of months (see this post) have validated our economic decision to not immediately install solar panels.  If we assume that our usage this past month is probably peak in Dallas (month of Aug/Sept), and even if we assume that we can eliminate this bill completely by installing solar panels, that gives us a best-case return of $3,480 per year.  That would allow us to get a 9 year payback on the $30,000 it would take to install the solar panels.  So…realistically if we assume that our electricity will actually cost us somewhere around $2,000 per year, and that we’ll only be able to eliminate 1/2 to 3/4 of that cost, the payback becomes something more like 20-25 years. 

Admittedly, I don’t know the ins and outs of the new federal tax implications of installing solar panels, but even if I get a break of 50% of the cost of the panels, a 10-12 year payback still seems a little long for us.

BUT!  We did have all of the conduit installed in the guts of the house to accommodate solar panels if/when we do decide to install them.

PS:  We use Green Mountain Electric, so even without solar panels we’re contributing to the promotion of green energy.

Our home has been selected by the Dallas Chapter of the American Institute of Architecture to be one of eight homes on the 2009 Dallas Tour of Homes.  The event is a great way to see some of Dallas’ newest and most amazing architecture.  We’re in great company – check out all of the homes that are on the Tour here (click on “Homes” at the top of the page). 

Accolades go to our architect/design team of Kelly Mitchell and Garry Walling.  This is Kelly’s second home on the Tour (she also contributed to a third home that was on the tour a couple of years ago).  Check out Kelly’s first one here.

If you take part in the Tour, you can actually see our house first-hand!  Buy a ticket!

PS:  I never mentioned that the tour is November 7th and 8th!

We received our electric bill today for the period of 8/5 to 9/4.  We used 2,384 kilowatt hours during this time period.  Our house is 3,501 square feet, which calculates to .68 kilowatt hours per square foot.  This is the most fair calculation I could think of to compare electricity usage in my own informal poll.  During this time period, the average high and low in Dallas were 96 and 76 degrees, respectively.

When I compared our usage to that of some of our friends, the typical non-Green home came in at about 1.3 kilowatt hours per square foot, just about twice our Green home.  It’s also important to note that the other homes I’m comparing to do not have a pool or electronics as extensive as we have…so our home is coming in even more efficient than the raw calculation shows.

Facts about our house:

• We keep the air conditioner between 73 and 75. 
• The main house uses two 21 SEER Carrier HVAC units
• The studio has a highly-efficient Daiken HVAC unit.
• We have the whole house ventilation system (ERV) on “intermittent”.
• The pool filtration system is on a timer, and runs 2 hours per day.
• We keep all of our entertainment electronics plugged in, but we turn off the Blu-Ray, speaker controllers, secondary DVR box, and printer when not specifically being used.
• Per an earlier post, we have a charging station (for iPhones, iPods, electric toothbrushes, razors, house phones, etc) that is switched on only when specifically needed.
• Because of all of our windows, we rarely turn on lights during the day.
• The house has approximately 17% fluorescent lighting, including the primary lights for the kitchen and most task lighting.
• The outdoor “moon lights” are compact fluorescent lamps.
• Appliances are Energy Star certified.
• Washer/Dryer are high efficient Bosch Axxis models.

On a related note, our actual bill this month was $290.62.  We use Green Mountain’s “Pollution Free” plan which charges us 11.7239 cents/kWh.  This per kWh pricing is a bit higher than traditional plans, but we believe it’s worth a slightly higher charge given that it’s supporting 100% Pollution Free energy generation.

I just got our gas bill for the month that straddles August/September.  It is $21.29.  We used 700 Cubic Feet of gas.  If you’ll review my post from a couple of weeks ago, you’ll see how we keep our gas bill down.

I also wanted to note that the charge for our actual gas usage was only 43 cents of the $21.29.  The rest of the charge is made up of a Utility District Charge (25 cents), Taxes ($1.45), a Rider Charge ($4.69), and a “Customer Charge” ($14.47).

Amazing how 43 cents worth of natural gas costs me $21.29!

I wanted to provide an update to the People Newspaper post that I created a couple of months ago.

The situation in Dallas remains the same:  there are no rules that regulate the use of rainwater in clothes washing machines.  I was informed by Lonnie Erwin, the Dallas Chief Plumbing Inspector, that the regs won’t be ready until the new fiscal year starts in October.  I’ve got a note on my calendar to send him an email on 10/1!

PS:  the photo is of our two 2500 gallon cisterns on the side of the house.

In a prior post I mentioned that our Home Provider (GWS) informed us that we have completed all of our documentation for the LEED certification process.  I thought I’d share a few tactics that we used to document our compliance where we were required to do so.  It might have been easier to compile this stuff as we went along had we understood the depth of information that was required.  Generally, our Home Provider accepted the following:

• Invoices/Purchase orders that clearly outlined the fact being proven (FSC Certification, specific framing orders, etc).
• Website links (that show local production, special certifications, etc).
• Google Maps (that prove distance to Open Spaces and Public Transportation).
• Spec Sheets (to prove characteristics of appliances, toilets, hot water heaters, HVAC systems, faucets).
• Photos (to prove specific installation facts – and also used to provide that we used 1.5 gpm flow rate aerators!).
• Statements from suppliers (we used this for our framing orders, local production, and FSC certification of framing lumber).

Generally, assume that you’re going to have to file proof of every point that you’re trying to get.  A helpful hint is that you should take a lot of photos of the house during each phase of construction.  Not only will it be helpful later when you’re trying to figure out exactly where that stud was placed, it will be helpful if you’re asked a question that you can’t remember the answer to because the walls have been closed up for 6 months!

Anyone have other helpful documentation hints?

Not sure how I missed this, but here’s a great summary of our project (and the website and this blog).  Thanks to the folks at The Surface Blog!

http://www.surface-blog.com/2009/07/being-green-is-gettin-easier-everyday/#more-1008

It’s the middle of summer so we don’t use much gas anyway, but I thought I’d give you an indication of how efficient our tankless hot water heaters are.  Our gas bill for the billing month that straddles July & August was $20.60.  We did/do a few things that help with the efficiency:

• Wash clothes mostly in cold water
• Have three tankless hot water heaters (one for each side of the house, and a small, on-demand one for the studio)
• Have very short runs between heater and faucet
• Bar with no hot water, only cold

In looking back at the rental house with a conventional hot water heater, our gas bill for last July/August was almost $30.00.   While that’s not a huge savings on gas in the middle of summer, it gives you an indication of how much you’re saving based totally on hot water usage….about 1/3 of your bill if you still have a tank heater.  And by the way, we rarely cooked at the rental house beyond a regular pot of oatmeal on Sunday mornings.  We’ve cooked more in the new house than we’ve cooked in our prior 6 years together.

Click here to see a newspaper article about the house.

I have a couple of things to say about the article:

• I’ve expressed my disappointment to the author of the article that the focus of the first half ended up being on the lack of available regulations for the use of rainwater in our washing machine.
• The Dallas Chief Plumbing Inspector has been extremely cooperative and attentive to the discussion, and has informed us that sometime in August or September regulations will be created that will address our situation.
• The lack of interior use of rainwater should not put our Platinum rating at risk.

Having said all that, there are some very good points in the article.  And it otherwise sheds a positive, informative light on our project.  On a side note, the print version has a great photo of the home’s living/kitchen space.

I’ve been having some conversations with our Home Provider about permeability. 

Because stormwater runoff is a bad thing (moving water with pesticides, fertilizer and general trash into the sewer system, local lakes and streams), LEED SS4.2 values permeability – meaning it’s a good thing for the rainwater falling on your property to soak into your property and not run into your neighbors yard or into the street.

LEED provides a graduated point system that ends with 4 points for 100% permeability.  Keep in mind that 100% permeability doesn’t mean you can have -0- concrete.  Rather the Rating System states that you have to have features that direct water falling on the impermeable areas to features designed to capture the water and direct it to an area where the water will be absorbed.

With this post I provide a photo of our back patio – designed to direct water to the spaces between the concrete pads (versus having a solid slab).  Also, next to the patio (and difficult to see in this photo) is a swale that keeps the water from running downhill into our neighbor’s yard. 

The key question that I’m discussing with our Home Provider is the driveway ribbons.  We specifically designed this drive for permeability purposes.  The current question is whether the space between the ribbons is sufficient to support the amount of runoff from the ribbons…our Landscape Designer is working on the calculations.