Zero Energy

The independent source for news, opinions, prices, ratings and more of what you need to know to build, buy or renovate a home that produces as much energy as the little it uses.


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Half the homes standing in mid-century have yet to be built. So if we're going to have a zero energy nation, developers need to build zero energy homes. Some builders have a track record of building, if not zero energy homes, then energy efficient ones. A number of regional builders stand out and may be a place to start if you're planning to build or buy in their territory.

National builders have been relatively less involved with building zero energy homes, but they need to be aboard if zero energy is to make it. The ten biggest builders represent 25% of the single family housing market and that percentage is expected to increase to 33% in the coming decades.

Regional Builders

1. Ideal Homes - OK

Builder of the near zero energy home in Edmond. Leader and award-winner in building affordable, energy efficient starter and move-up homes.

2. Clarum Homes - CA

Long experience in building very energy efficient upscale homes. Rare builder that incorporates passive design in development homes and installs solar panels as standard equipment.

3. Carl Franklin - TX

Builds highly energy efficient homes across the price spectrum. One of the few developers with extensive experience building with structural insulated panels and in installing geothermal heat pumps - 2 incredibly desirable features of zero energy homes.

4. Geos - CO

Building a zero energy development of 250 homes with electricity provided by solar energy and heating and cooling supplied by geothermal heat pumps. Homes to be ready in 2009. Prices: $200,000 and up.

5. Artistic Homes - NM

Just built a 1,666 square foot home with a Home Energy Rating System Index of 0 selling for $258,000. Building another HERS 0 at 2,158 square feet for $291,000. Developers insist they will build a zero energy home for anyone with the money to pay for it and that in its latest development all the homes will be HERS of no more than 57 (i.e. Energy Star = 85, Standard home = 100; average U.S. home = 130).

. . . . more to come.

National Builders

Here's a list of the top ten builders, according to Builder magazine, but with links provided only to the three in italics that devote any space to energy efficiency on their web sites:

1. D.R. Horton

2. Lennar

3. Pulte*

4. Centex*

5. KB Homes

6. Hovnanian

7. Beazer

8. Ryland

9. NVR

10. MDC

* Centex, which has built a (near) ZEH, and Pulte finished one, two in customer satisfaction in the latest J.D. Power Survey. Now the two companies have merged to become the country's largest home builder. Now isn't that a coincidence? (They still maintain their own web sites.)


Federal, state and local governments have shown varying degrees of interest in zero energy.

Federal Government

Sing "Be All You Can Be" and everyone will answer: "The Army!" But how many people know "marketable zero energy homes by 2020"? Not many, but the U.S.Department of Energy Office of Energy Efficiency and Renewable Energy's Building Technologies Program, including its 14-year old Building America project, is working to achieve it. Obviously, the program has been modest in calling attention to zero energy and, as they say, the DOE has much to be modest about. It gets A+ for long recognizing the need, but it has had a hand in few, if any, zero energy homes or in making them possible. Money? Legislation or regulations promoting ZEH? What? Where? Its web site is loaded with information however, much of it useful. To take a look click here.

The IRS however, will give you tax credits. You can get a 30% tax credit on a solar installation. Geothermal gets the same 30%, but with a cap of $2,000 for a home owned by a single owner and $6,667 for a home owned by more than one owner.

State Government

Strength lies in offering rebates on renewable energy equipment, mostly solar, but sometimes geothermal. A number of states offer enough money to cut the cost of solar installations more than half. Click to the solar and heating pages on this site to learn more and to tap into the funds.

Local Government

1. Austin, Texas

Starting in 2015, building codes call for making every new home built in the city zero energy capable. That means, they have a schedule of measures to reduce consumption by 65% and homeowners can then install solar installations that will produce the equivalent of the remaining 35%.

. . . .more to come.

Other Resources

Zero Energy Home Plans sells a variety of home building plans that it says will enable you - with a builder who will work with them - to build a zero energy home. The plans sell for around $1,000 to $1,500. To see what plans the company has click here.

Zero Energy Bellwethers To Watch:

By their performances, small public companies may give us an idea about how serious we are about reaching zero energy.

In capitalism, what works, what's good, what's accepted is what sells. That may be a touch cynical, but nevertheless it's hard not to think that if those companies that only produce products or provide services essential to achieving zero energy do great then we are on our way towards becoming the zero energy nation we must be. Put another way, if they all do poorly, it'd be hard to think we're winning the war against global warming.

To be sure, there are lots of other reasons that could cause a company to go under or limp along. To cut off that possibility, I've picked a number of solid companies. By solid, I mean they're all established companies with a generally consistent record of increasing sales. They're also all public companies with stocks selling on major exchanges for generally $10 or more per share.

This is not a particularly high bar - except for pure green plays. Many are companies that haven't been public for long. They may be penny stocks or listed on small exchanges. Earnings may be only something management dreams about.

I will largely track sales and earnings. Since the latter is a difficult concept even for some of my companies, the former will, as I said in the beginning, be the main measure of progress for the companies - and energy efficiency or renewable energy.

CREE The Durham, North Carolina based company produces semiconductor material used in light emitting diode (LED) components and lighting. LED are about 80% more energy efficient than incandescent lighting and are a big favorite to replace incandescent bulbs as they are phased out. The company makes its own LED and provides material for General Electric bulbs.Roughly 90% of revenues come from LED products. The rest from radio frequency products made from much the same materials as LED. Sales for the last 5 years were (i.e. in millions): $567 (2009), $493 (2008), $394 (2007), $423 (2006), $385 (2005)

SUNPOWER The San Jose, California company makes solar cells, panels and inverters. Its monocrystalline panels are among the most efficient collectors of solar energy in the world. They're used in both large-scale solar projects and single-family homes. However, there are competing technologies and if by chance they become better deals Sunpower could suffer even if solar takes off. Sunpower sales for the past 5 years (i.e. billions): $1.52 (2009), $1.44 (2008), $.77 (2007), $.24 (2006), $.08 (2005)

ORMAT The Reno, Nevada company designs, develops, builds, owns and operates geothermal power equipment and plants in the U.S. and abroad. Looks to set up operations where it's easiest to tap the earth's heat, as in the western states, which currently limits its potential. Sales for the past 5 years (i.e. in millions): $415 (2009), $345 (2008), $296 (2007), $269 (2006), $238 (2005).

COMVERGE The East Hanover, New Jersey company produces and provides "Smart Grid" technology for home, utility and commercial uses. For the home, it produces "smart" thermostats that can help homeowners keep track of their energy use. Similarly, for industrial, commercial and utlity use its products help in adjusting energy loads and manage energy use more efficiently. Few green subjects enjoy wider support than "smart grid". However, Comverge's tiny size could be a handicap in competing with bigger players - making it a possible takeover target. Sales over the last 5 years (i.e. in millions): $99 (2009), $77 (2008), $55 (2007), $34 (2006), $23 (2005).

Zero Energy Homes Dateline: 2020?

In Europe and the U.S. rules, regulation and talk come tantilizingly close to setting a timeframe for building homes that produce as little energy as they use

They parse words, but put them all together and it comes to the same thing. Government is calling for new homes with solar energy installations on the roof that provide as much energy as the home uses.

Austin Texas has adopted building codes requiring that new homes be "zero energy capable" by 2015. In the United Kingdom, they must reach Code 5 or one step below Code 6 - the zero energy level - by 2016. The European Parliament passed an initiative requiring that all new homes built starting in 2019 must be zero energy and the U.S. has long had a goal of making zero energy homes "marketable" by 2020.

How likely are the chances that zero energy homes will be a reality in ten years? It's hard to say, but just a few years ago no governments had proposed anything. There was only the standard U.S. goal from the nineties. it certainly seems possible that zero energy homes could register a significant percentage of new home construction in a decade within reach of middle income families.

Indeed, the models for tomorrow exists today. There may even be some initiatives following government leadership. A zero energy community is being planned for Austin. The illustration above is an example of what its developers hope to build.

Nor does government have to lead the way. Some private builders may show their own initiative and, if fact, some builders have already made the zero grade. Now all they need is a year or two of zero utility bills.

Year 1 For Affordable 0 Energy?

When the housing market gets back on its feet we just may have by then a niche for production homes so energy efficient their owners don't have any utility bills to pay

Take a look at the two homes below. The blue one is in Townsend, Massachusetts and the sand-colored one is in Rio Rancho, New Mexico. They don't look at all alike, but they have a number of things in common you'd be hard pressed to find in almost any homes in the country.

They were built by commercial builders for sale at relatively unexceptional prices for the area they're in. The Massachusetts home is priced below $200,000 by Transformation Inc. and the New Mexico home was priced at $258,000 by Artistic Homes. They're also both electric homes connected to utility lines, but they should use no more electricity than they produce.

Neither has proven yet that they are in fact net zero energy homes. They were only built within the last year and have not racked up a year's worth of being lived in. Without that, you can't be sure that the house will produce as much energy as it uses.

Nor are they perfect. The Massachusetts house has, as you can see if you look closely, double hung window, which you can read elsewhere on this site is wrong for zero energy homes. The New Mexico sullies the spirit of zero energy with the prominence it gives to cars with the garage front and forward for housing a presumably gas-powered car.

However, the two homes have earned zero energy ratings. That is their Home Energy Rating System index rating (HERS) equals 0, which means that under average living conditions a year's worth of utility bills should be offset by the power produced by the solar panels you see on their roofs. By comparison, an Energy Star home has an 85 rating; a standard new home 100; and an average home 130. So a zero rating in itself has them standing far apart from the vast majority of American homes.

It's not that zero energy doesn't exist. Indeed, when I started this site last year, I ran across off-the-grid, custom-built, government sponsored, nonprofit subsidized and near zero energy homes. I talked about these efforts too in the story below this one. We were getting close to making a business of affordable zero energy homes, but I hadn't found any.

But times are changing. I have blogged about a number of commercial zero energy projects getting underway across the country. If there is this much zero energy activity among commercial builders in the housing tsunami we're in, can we not be optimistic about a zero energy niche being developed by builders across the nation?

Hopefully, updates will uncover successful developments and proof that zero energy is for real. In the meantime, consider where I started out as a measure of how far we have come in such a short time:

To A Higher Standard of Living

We're within reach of being able to make every home so energy efficient you'll never have to pay a fuel or utilities bill again.

Start with the home at 2508 N.W. 180th Street in Edmond, Oklahoma, then see similar single-family houses in Longmont, Colorado, Tucson, suburban Los Angeles, San Diego, Pittsburgh, Lakeland, Florida, Perkiomenville, Pennsylvania and elsewhere around the country.

The Oklahoma home, which is a new house, and the Colorado home, which is an older one, are pictured below. They look different, but the two houses and all the others have something important in common for the times we live in. They were built or renovated with zero energy in mind: a goal of having no utilities bill to pay.

While few make it all the way, you begin to get the idea that zero energy homes are within reach across the country at a price many Americans can afford to pay. It's still a huge job, made bigger now by a weak economy in general and a depressed housing market in particular, but one that needs to be done. Simply put, zero energy should be the housing standard and every homeowner should meet it.

Zero energy homes (ZEHs) is housing's energy efficiency end game, the highest and sturdiest standard we have available. Achieving it will take our homes out of the equation as major contributors - about 20% of energy use (blue in pie chart) and carbon emissions (not shown, but similiar breakdown) - behind global warming and the skyrocketing energy costs that have taken the widely reported turn for the worse recently. It will also help in reducing commercial consumption (red) because all buildings face similar energy challenges.

A Good Deal for Homeowner Gets Better

Zero energy is also a good idea for many individual buyers and builders now. Indeed, if homeowners didn't have to pay energy bills this winter they would be saving more money than in any year before - good twice over when family budgets are already strained.

It's not that ZEHs run on air. They use energy, but they also produce as much as they consume - though I prefer "little" so the emphasis is on low consumption not high production.

Buyers and homeowners may show a net gain on the expense of making a house zero energy efficient. How? Take out a loan. It can be either through a larger mortgage when buying a new home or a line of credit when renovating or retrofitting an existing one. You come out in the black each month if your utilities savings are greater than your monthly loan payments.

The timing on financing is good too. We're in a low-interest rate environment and borrowers can lock in favorable rates and monthly payments. At the same time, energy savings are virtually guaranteed to increase because fuel prices rise over the long run and most likely at an increasingly steeper rate.

Near zero energy home built in Edmond, Oklahoma: one of a developer's standard models transformed (though little is visible).

So whatever the savings and payment picture looks like now, it will only get brighter. Payments will remain flat while savings get bigger. In addition, making a home more energy efficiency as with any capital improvement increases the value of the house.

Homeowners may see improvements on the cost side too. Energy efficient equipment and material will get cheaper because of the economy of scale as more zero energy homes are developed. Owners may also be able to count on rebates and tax credits which are offered in some form in most states for making homes more energy efficient because of the need to reduce the high cost of supplying power to homes.

The advantages of zero energy homes are not limited to finances either. They're also quieter, more solidly built and more comfortable than the traditional energy-wasting house.

Getting to Where We Need to Be

The object of this site is to help make zero energy a reality in every home in America. The method of this madness is to cover the subject to see what makes a ZEH and what's the easiest, cheapest and most intelligent way to build a new one or turn an existing house into a ZEH.

Raising awareness and comfort level would be a good first step. A 2004 National Renewable Energy Laboratory study found that one barrier to increasing the number of ZEHs is a lack of familiarity and an abundance of apprehension. Builders and buyers alike didn't understand or doubted what benefits they would be getting for their expense and how it would be worth it to them in the long run.

An existing home in Colorado retrofitted to near zero energy standards (though appearing the same before and after).

It isn't likely there's been much change in those views since then. First-time home buyers never mentioned energy efficiency, much less zero energy, when asked why they bought their houses, according to a housing study released this year by the National Association of Home Builders. Quality, in sixth place behind price, layout, size, yard and exterior, was the closest they got.

To be sure, a much faster way of getting people into at least new zero energy homes would be to make all the features of one required by buildings codes. If using codes is seen as too forceful, then the features could be made part of standard building practices and require a buyer to opt out of them before building starts. In any case, zero energy should be just as much a standard feature of a home as electric light is.

Zero energy should be just as much a standard feature of a home as electric light is.

It might be done in steps too. For example, it could be required or standard for homes built over a certain period to reach familiar Energy Star levels of efficiency for the entire home or just appliances - a mere 15% to 20% more efficient than current standards. That alone would be a big step in the right direction. Less than 1% - about 750,000 homes - of the 80 million single-family houses in the U.S. are now Energy Star homes.

Going on to zero energy would mean an even bigger leap forward. Zero energy homes number, by some estimates, no more than just a few thousand houses.

Everything You Need Right Off The Shelf

Ironically, zero energy is meant to be thought of as simple, ordinary, average and familiar. Everything in a ZEH that makes it as efficient as it is comes off the shelf. Nothing hi-tech or revolutionary. ZEHs just have the most efficient materials, equipment and appliances used in the most efficient way. The ones this site will focus on include insulation, windows, space heaters, central air, hot water heaters, lighting and refrigerators.

Key Words

Insulation, Windows, Space Heaters, Central Air, Hot Water Heaters, Lighting, Refrigerators and Solar Energy Equipment

To be sure, these are not the kind of things, with the exception of the refrigerator, most people pay much attention to or know much about however efficient they may be. Also, some of the most efficient energy users and savers may be found on fewer rather than as many shelves as the less efficient variety because they cost more and are not in as much demand. That's why this site, at least initially, will limit the hunt to the users and savers mentioned above. They are the biggest energy users and savers and the idea here is to keep it as simple as possible.

How they are combined and how efficient each one need be will vary depending on the home, climate, prices and budget. It's also - it must be emphasized - a package deal and, for owners of existing homes, it may be best completed over time. You may not need or it may not make sense to get the most efficient products to achieve zero energy.

You decide for yourself and do the work too, but in many instances home owners and buyers will need to huddle with builders and contractors to determine what works best. This site hopes to give you enough information about insulation, heating and the like so the conversation will be an intelligent one.

Same Houses and Lifestyle (for Most People)

The goal is to reduce consumption of the average house by 70% to 80% without forcing any changes in a homeowner's lifestyle. In fact, energy consumption may be reduced more if not for the allowance of the electronics - computers, printers, microwaves, battery charges, etc. - found in today's home. They will account for much of the remaining 20% to 30% in energy usage. (Stand-by power alone accounts for 10% of home energy usage).

Exactly how much you'll be able to reduce consumption and your energy bills will depend on your house, its location and energy use. For example, the average U.S. home has utilities bills totally about $2,000 and if it were made 80% more efficient that would bring the bill down to $400 - about all that should be left to pay by any homeowner. A house loaded with electronics that is larger than the median of 2,277 square feet (i.e. more space to heat and cool) and where lights are left on all the time will struggle to reach this utilities cost level. A smaller home with fewer and less powerful energy users will have an easier time.

A zero energy goal of having a modest solar energy installation provide all the energy a home needs, but bet on smaller houses to make it.

It's not, of course, a zero energy home yet because however much is used still has to be offset by equal amount energy production. For the median home above that would be $400 worth of electricity. The electricity produced - in virtually every instance - by solar panels at the home during sunlight hours would be sent through the same lines it comes out of from the electric utility and credited to the homeowner's account so at the end of the year, if not the day, the bill is zero.

Strictly speaking, you can have a zero energy home without reducing your energy consumption. You just buy enough solar equipment to produce enough energy to offset the entire $2,000 average annual in an average home or whatever amount you use. This however would be incredibly expensive.

Solar power equipment and installation is likely to be the most costly part of zero energy home. You may wipe out your energy bills with a huge solar installation, but if you financed the efficiencies and the solar equipment through a loan your monthly finance charges will far outstrip your savings. You also won't be doing as much as you could to help cool down the planet. In the end, an installation that can produce the equivalent of about $400 worth of electricity is in the ballpark in terms of what many Americans can afford.

Zero energy homes exist off the grid too, but it's likely to be a less attractive alternative for most homeowners. Owners of off-grid zero energy homes are able to provide their own energy all the time only by storing their electricity in large lead acid batteries. Lead is a hazardous substance and its properties raises issues of safety, disposal and the cost of producing the metal.

The batteries are also expensive and the whole system is more complicated than a grid-based one. It's likely to appeal mostly to rural do-it-yourself homeowners.

Zeroing In On A Menu of Choices

The table below has 4 homes and a short preview or snap-shot of the kind of energy savers, users and producers each of them might have. You'll find a nuanced discussion on each page of the web site.

You may also find the table useful in putting together a ZEH package. For example, triple pane windows will help a home reach zero energy better than other windows, but it's not required. In fact, it may be possible to find a single pane window in a ZEH. Perhaps you found that you rather spend the extra money a triple pane costs on more resistant insulation.

The details you'll find on each web page of this site include the names of brands, efficiency ratings, shopping locations, licensed contractors and prices - mostly, for the time being, from the Internet.

Zero EnergyNear ZeroEfficientStandard
InsulationDepartment of Energy Recommended LevelsLatest International CodePrevious International CodeNo International Code
WindowsTriple PaneDouble PaneDouble PaneSingle Pane
HeatingHigh Efficiency Geothermal Heat PumpGHPEfficient BoilerFurnace
CoolingHigh Efficiency Geothermal Heat PumpGHPEfficient Central AirStandard Central Air
Water HeatingVarious Combinations (i.e. Geothermal, Indirect, Tankless, Solar Thermal)TanklessEfficient StorageStorage
LightingLight Emitting Diodes and StandardStandardStandardStandard
AppliancesHighest Energy StarEnergy StarEnergy StarNot Energy Star
Energy ProductionSolarSolarNoneNone

Putting A Label on It

One way to make zero energy homes look good is to require home sellers to put a label on their house that has a check list of various type of heating and cooling equipment, insulation, windows and other "ingredients" that affect energy efficiency arranged from most to least efficient.

That way, the zero energy home would be the ones that have the most boxes at the top checked off. Put the label in a frame attached to the front door of the house and potential buyers would get a good first impression of the home. They might even be ready to buy it even if it does cost more than similar, though less efficient models.

Here's an example of one and you can find out more about the "ingredients" or details on the other pages on the site:

The Franklin

1970 First Earthday Drive

Heating and Cooling Equipment:

Energy Star Geothermal Heat PumpEnergy Star Geothermal Heat Pump
Natural Gas Condensing Boiler (90% AFUE or higher) Energy Star Central Air (14 SEER or above)** 
Boiler (78% AFUE* to 89% AFUE) Central Air (SEER below 14) 

*Minimum Annual Fuel Utilization Efficiency required for all new boilers and furnaces; **Seasonal Energy Efficiency Rating minimum for Energy Star rating as of January 1, 2009


R-30** R-13 R-13 None 
None None None None 

*Resistance to heat transfer level recommended by Department of Energy, but not followed by any states (i.e. entire row); **Latest International Energy Conservation Code (2006) insulation standards and followed by 18 states (i.e. entire row).


Double Hung (14)*
Under U-.25**
U-.25 to U-.50 
Over U-.50 

*Type and number of windows. **The U-factor is the inverse of the R-value: Smaller is more efficient.

Home's Orientation:

Within 45° N/S 
Over 45° from N/S 

*South face should generally have the most window surface area.

Hot Water Heater:

Geothermal, Solar, Indirect*

*Each offers parttime help to fulltime tankless or storage.


Annual Energy Use
Under 400 Kwh*
400 Kwh to 450 Kwh** 
Over 450 Kwh 

*Largely limited to top freezer models under 19 cubic feet capacity; **Same, except 19 cubic feet to 21 cubic feet capacity.

Home's Frame:

Wood Type
FSC: new construction option 

*Forest Stewardship Council certified (i.e. responsibly managed forests)

Solar Photovoltaic:

PV Installation
Not available 

*Minimum 2 Kw; 6 Kw suggested maximum.

Beating The Market?

A zero energy home can be your best investment, even in this economy.

Homeowner Alan Williamson tells the story on PBS's Nova and elsewhere of how he's effectively netting the return from a certificate of deposit on a loan he used to turn his house into a zero energy home. The 4-decade old suburban Los Angeles 2,300 square foot tract house was costing him $6,000 in utilities bills (annualized) when he decided to make the upgrade soon after buying it in 2003. He borrowed $43,000 to do the work over 2 years and is pocketing the difference between the $6,000 he isn't paying to his utilities company and his loan payments (i.e. $4,250 annually at today's rates over 15 years).

Besides the extra cash, which would work out to about a 3% or 4% pretax return on the $43,000, depending on the terms of the loan, he'll have the home improvements that will last many years and the savings which will go on and on.

Williamson doesn't think everyone can do as well as he did financially. Indeed, they're unlikely to have the motivation of so much potential savings. His utilities bill was 3 times the national average. So what if you live in a house with ordinary bills and you don't have so much to gain?


Let's see how it works out by borrowing money, as Williamson did, and by paying up front.

We know what we expect to get out of this. It's not having to pay the average $2,000 annual or $167 per month gas and electric bill that the average American pays (i.e. gas and electric is found in a majority of homes), according to figures from the DOE's Energy Information Administration.

However, coming up with a figure on the cost of transforming a typical house into a zero energy home isn't that easy. As there aren't too many ZEHs, there is nothing typical about them. It's all anecdotal, so far, so let's just use the same $43,000. It could be higher. California is sunny and has rebates so you're going to get more for your money on the energy production end. It could be lower too. The cost of living is higher around Los Angeles than many parts of the country and older homes often require more work.

Still, the house is only a few square few away - 23 over to be precise - from the median, which is an important factor when trying to decide what's a typical home.

To be sure, conventional wisdom says you'd have to perform a lobotomy on most builders and buyers before they would accept such a deal or anything remotely close. As David Wilson, then-president of the National Association of Homebuilders said in 2005 while objecting to proposed building codes improvements that called for increasing insulation levels: “For every $1,000 increase in the cost of a new home, more than 240,000 [sic] potential home owners are priced out of the marketplace.”

But wait . . . .

Paying up front can be seen as buying 1 share of a stock that issues a regular dividend. That is, you get a return of $2,000 annually on your $43,000. Using the following dividend yield calculator your return is over 4%, pretax or as good as a CD and much better than stocks over the past year. Of course, your utilities bill may differ just as easily as the cost of the upgrade will. Williamson would be earning 14% had he paid $43,000 instead of borrowing it, but the point is you're going to get a return on investment. It may take a long time to recoup the cost/investment - maybe much more than Williamson's 7 years - but in the meantime you're enjoying the benefits of a zero energy home. It's a stronger, quieter, more comfortable house with a higher resale value that is contributing next to nothing to global warming.

Figures vary wildly on how much of the cost of energy efficient improvements return when a house is sold, but 50 cents on the dollar is a reasonable figure. That's less than a good coat of paint, but more than a swimming pool.

How about with the loan?

You can get a bigger mortgage on a new home or take out a line of credit or a home equity loan on an existing home. Using a mortgage calculator for a 30-year fixed rate on the $43,000 added to your mortgage means paying an extra $248 a month less the $167 utilities savings increases your monthly home payments by $81 or $972 a year.