WEB EXCLUSIVE

In November 2001, my wife, Heather, and I purchased a property in Jaffrey, N.H., that supports two households in two old buildings — a 3,200-square-foot, two-floor main house and a 500-square-foot free-standing, one-room-with-loft rental cottage. In our first four seasons of occupancy, April 2002 to March 2003, the two households consumed 322 million British Thermal Units (Btu) of fossil fuel energy.

Since then, through conservation, passive solar techniques, the installation of solar systems and the use of wood stoves, we have achieved an 81 percent reduction in our two-household use of fossil fuel-derived energy. And despite adding 335 square-feet of heated living space, our energy use from all sources is down by 44 percent. In 2010-2011, I've projected that we'll use just 63 million Btu, dramatically reducing our CO2-equivalent emissions.

To put that in context, our sprawling 96-year-old house now consumes less than half the fossil fuel energy of the average New England household (see energy use tables at eia.doe.gov). And the consumption of fossil fuels by our property's additional cottage household is much lower than at the property's main house. Our total energy use per household from all sources — including our active solar and our cordwood — is now about equal to the New England average.

When we took occupancy in 2001, the main house included unheated attic and basement spaces. The basement spaces were mostly below ground level, except for a basement entrance way at the northwest corner. An unheated 190-square-foot screen porch cut into the first floor's northwest corner, allowing cold weather and wind to reach into the house beneath the second floor. Most of the house's heavily used living spaces were at the north end of the house, receiving little sun and requiring artificial lighting during the day. An ineffective solar thermal hot-air collector hung from the southeast edge of the north roof.

All first- and second-floor exterior main house walls contained 4 inches of blown-in urea-formaldehyde foam insulation (old enough to be inert and no longer dangerous). Fiberglass batts had been loosely installed between the joists below the first floor. Attic floor insulation included loose rock wool between the joists and 9-inch fiberglass batts over most, but not all, of the attic floor planks. The house had leaded single-pane windows throughout, each with a removable interior storm window.

Heat for the house was provided by a baseboard system using forced hot water from a dual-fuel, oil- and wood-fired boiler. Five heating zones (one in the basement crawl space) used adjustable thermostats to call independently for heat. Domestic hot water was primarily provided by the boiler; an electric water heater was in place as an alternative for warm weather use. A large wood stove sat in a fireplace in the central dining/sitting-room area. There were five additional working fireplaces.

At the cottage, an electric baseboard heating system had been installed, along with a propane heater and a wood stove. There was rotten fiberglass insulation between the floor joists in the unprotected crawl space below. The walls and ceiling appeared to be insulated. It had no storm windows.

We took several steps to increase energy efficiency in both our home and the property's cottage.

Insulation, Isolation and Passive Solar: We enclosed the first-floor northwest screen porch with removable glass panels and insulated doors. This change transformed this weather-exposed area into both a buffer from the outdoor cold weather and, in the afternoon, a significant source of passive solar gain for our living room, which is at the north end of the house. At the same time, we installed an efficient Jotul stove in the living room fireplace, enabling us to warm this area — one of the house's separate heating zones — without turning on the central oil-fired heat.

We also added fiberglass insulation to attain about an R-45 level of insulation in the house above the second-floor ceilings. We applied spray-foam polyurethane insulation to exposed basement walls to stop cold air infiltration. We've also used this foam insulation to achieve an R-28 insulating value in key first-floor walls. At the cottage, we have applied spray-foam insulation to the underside of the exposed plank floor.

Windows and Doors: We have added storm windows at the cottage and good storm doors at both houses. We have installed insulated roman shades and insulating honeycomb shades in selected main house windows. In January, we installed Window Quilt insulating shades (1windowquilt.com), rated at R-7, on all windows on our passive solar porch.

Appliances: We no longer use our electric clothes dryer. Instead, we use clotheslines outside or an indoor foldable wooden rack, which we place near our main wood stove. We have switched from large desktop computers to laptops. We have learned to use a power strip to fully turn off our TV when it is not in use. In general, we try to unplug any appliances that consume unnecessary electricity even when switched off. We installed an energy-efficient refrigerator in 2004.

Lighting: A key component of our renovation work through the years has been to bring natural daylight into the house. This has greatly reduced our use of electric lighting. Also, we have switched to compact fluorescent bulbs (CFLs) in most locations in the house.

Sub-Metering: We have used a Watts-Up plug-in sub-meter to identify patterns in our use of electricity. In 2007, we installed a hard-wired sub-meter for the cottage, allowing us to bill the tenant for his use of electricity. This set in place an incentive for minimizing cottage electricity use, and, of equal importance, enabled a more precise understanding of the differential use of electricity between the house and the cottage. Last December, we added a TED (The Energy Detective) sub-meter that allows us to monitor selected hard-wired circuits. We are currently using the TED meter to measure our hot water electric energy use.

Wood Stove Heat at Cottage: The cottage is now exclusively heated by its wood stove.

In 2004, we replaced the house's old heating system with a high-efficiency Buderus oil-fired boiler system (180BTU BUDG215/5). It includes an electronic control system (Buderus Ecomatic R2107 Control) and a nine-zone supply capacity. At the same time, we installed a 70-gallon Vaughn Top Performer super-insulated indirect hot water tank, which was heated using the Buderus system.

We connected this new heating system to seven thermostat-controlled heating zones in the house, designed to conform to our anticipated house-use patterns. An eighth zone was dedicated to domestic hot water, and a ninth zone was reserved. Later on, in November 2009, we switched to an anti-freeze fluid for the oil-fired boiler system. We have also insulated most exposed heating and hot water pipes in the basement.

The targeted heating enabled by this system allows us to safely turn down the heated temperature in infrequently used parts of the house to 40˚ to 45˚F (about 4˚ to 7˚C), down from the 55˚F (about 13˚C) level we had thought necessary to maintain before. At these low temperature settings, the central heat rarely kicks on. But those areas may be readily heated to higher temperatures when family and guests are visiting.

Remodel Adds Space but Reduces Energy Use

In 2004, we converted several small rooms at the south end of the house to a study on the second floor and a master bedroom with bath on the first floor. Both areas have solar exposures to the east, south and west. We added spray-foam wall insulation and insulated windows in the master bedroom area, while preserving the existing windows and urea-formaldehyde insulation on the second floor.

We added a 190-square-foot solar porch, with a 5-inch concrete slab and frost wall that we insulated below ground on all exterior surfaces to R-20 using styrofoam board. The porch wraps around the southwest corner of the master bedroom and adds 248 square-feet to our interior heated space. Double-pane, energy-efficient windows and doors enclose the porch. The ceiling is insulated with spray foam polyurethane to about R-60. At the wall between porch and bedroom, we brought natural light into the bedroom from the south and west by adding double-pane, energy-efficient windows with sills at waist height and an insulated, exterior grade, glass-paneled door. We had brought two small wood stoves from our previous home. We installed one of these in the existing master bedroom fireplace. We installed the other in a second, interior study on the second floor that adjoins the south end study.

The two second-floor studies form a single heating zone, isolated by doors from the rest of the house, with heat from the central boiler system supplied to the space through baseboard heat. For the master bedroom and solar porch spaces, we established three heating zones: one for the solar porch, one for the bedroom and one for the connecting bathroom. By closing doors, these areas can be isolated for heating purposes from one another and from the rest of the house. The solar porch has radiant heating coils embedded in the concrete slab, and the bathroom has separate coils stapled up to the floor from the crawl space below. We were able to retain the old baseboard heating lines in the bedroom.

The development of the master bedroom, study and solar porch spaces has had wonderful energy-saving effects. Electric lights are almost never needed during daylight hours. Even on the coldest winter days, the south study will be warmed to a comfortable temperature when the sun is out. And the middle study is quickly warmed by its small wood stove whenever needed. Due to the favorable thermal effects of the solar porch - effects that have recently been enhanced by Window Quilt shades and supplementary radiant heating from the solar thermal system - central heat is rarely needed for either the master bedroom or the porch. A small dose of wood stove heat in the winter evenings has been enough to bring the bedroom up to a comfortable temperature.

In 2004, we converted the three small rooms that comprised the first floor middle section of the house to kitchen space. We also built out that space by 6 feet to the west, converted the old kitchen area to a mudroom/entrance area plus half-bath and opened the new kitchen and entrance areas to the adjacent dining and sitting areas. This project added 87 square-feet of new heated space, a negative from an energy standpoint. But we were able to insulate the east and west walls of the new kitchen to about R-28 with polyurethane spray-foam insulation. We also insulated with fiberglass to about R-54 above the ceiling of the kitchen addition. A new double-pane, energy-efficient 20-square-foot window facing west from the kitchen addition brought in daylight and, in the afternoon, passive solar gain. Similarly, two relocated, leaded windows, each about 12 square-feet, with good interior storm windows, brought in daylight from the east and, in the morning, passive solar gain.

For this entire zone, now containing about 500 square-feet of floor space, we changed from baseboard to radiant heat from the main boiler, with the radiant heating coils stapled up to the floor boards from the basement and crawl space below. We also installed a new, efficient Jotul woodstove (jotul.com), replacing the inefficient stove that had come with the house. When in use, either system, woodstove or radiant central heat, is more than capable of independently providing ample heat for the entire zone.

As with the upstairs study, the development of this large kitchen and living area has had a major impact on our use of energy. Much of our time in the winter is spent in this area. Our use of electric lights during the daytime is significantly reduced by the natural lighting that comes in from the east and west. And for almost all of the hours that we are using the area, our heat comes from the wood stove. By closing doors that were added as part of the 2004 project, we are able to isolate this zone from the rest of the house, enabling us to minimally heat those other areas when they are not in use. In January 2010, we added insulation to the dining room ceiling in an area where only wood floor planks had separated the downstairs area from the second floor. This will improve the thermal isolation of the space that we are heating on the first floor.

In May 2008, we enlisted Solar Works, a Vermont company (now re-named Alteris) to install a grid-tied, 5.1-kilowatt (kW) solar photovoltaic (PV) system on the roughly south-facing 360-square-foot roof of our garage. The system has 24 Sunpower SPR-210 High Efficiency PV modules, each 61.39 in. x 31.42 in., in three strings. They are secured on the roof by a UniRac Solar Mount rack at the same pitch, 35 percent, as the roof. The panels face very slightly to the west of true south. The SPR-5000m inverter is located inside the garage. The system has a revenue grade meter and connects to a service box in the garage. The box supports circuits to serve electricity needs in the garage, including a table saw and various other power tools, and connects to the main service box in the house via a #6 wire through a roughly 100-foot underground conduit and then along the basement ceiling to the house service. The system is approved for net metering by our utility company, Public Service of New Hampshire (PSNH).

Annual production by the system so far has been about 20 percent less than that projected by Solar Works, roughly 5,250 kilowatt-hours (kWh) instead of the projected 6,500 kWh. The projection may have reflected a failure to accurately gauge the degree of shading from the east - or perhaps we have just been through a cloudier than usual period of time. Nonetheless, we are quite happy to have produced 5,250 kWh last year, and expect that continuing work on the shading and better weather will lead to higher production in the current year.

In May 2009, we installed a super-insulated 50-gallon Marathon electric water heater (MR502450), having determined that our indirect oil-fired hot water was inefficient. Then, in November 2009, we added a solar thermal system, using our new electric hot water heater as the backup tank and our existing 70-gallon Vaughn Top Performer indirect water heater as the solar tank. The solar components and installation specifications were all provided by Radiantec, a company in Vermont that is specially oriented to provide systems and technical support to do-it-yourselfers. We enlisted our local plumber, Keating Plumbing & Heating, the same company that had installed our heating system in 2004, to put the system together. The project was concurrent with a long overdue re-roofing of our house.

We installed three, 4-foot by 8-foot, Alternate Energy Technologies AE-32, glazed flat-plate solar thermal collectors on the east-southeast facing roof of our main house. With the help of our roofer and a rented 61-foot aerial lift, I raised the three, 113-pound panels to the roof and fastened them to struts bolted through the roof to the interior joists, tilting the collectors up by another ten degrees from the 40 degree roof slope to maximize solar gain from the eastern sun in the winter and swing seasons. Our plumber did the rooftop soldering from the lift. We ran the copper supply and return pipes down through the attic and closets on the second and first floors to the point of connection to the solar tank in the basement.

Temperature sensors on the roof at the supply side of the collector array and in the basement on the return pipe connect to a solar loop control, which turns on the circulating pumps when the triggering differential in temperatures is reached. A heat dump mechanism completes the system, protecting against overheating in the summer. We charged the system with an antifreeze solution. All circulating pipes are insulated with high-temperature pipe insulation.

We also connected the solar thermal circulating system to the master bathroom and passive solar porch radiant heating loops. We made these radiant heating and domestic hot water connections independently reversible, so that by opening and closing valves, we would be able to send the heated fluid from the roof to any combination of one or more of the solar porch, the master bathroom or the domestic hot water loops. This capacity is now enabling us to store significant heat energy in the mass of the solar porch's concrete slab. On cold nights and on intermittent cold, cloudy days, we are drawing noticeable heating benefits from this stored energy.

In the winter months, the collectors' eastern orientation means that there are only a few good solar hours each day to work with. But even with this restriction, we found that, in those winter months, our solar tank was often doing more than half of the work needed to provide us with 120˚F (49˚C) water, resulting in a significant drop in the kilowatt-hours used by our backup electric water heater.

Now, in March and April, with longer days, but also with outdoor temperatures still dropping into the low 30s at night, the thermal system's performance is much better. Most days, we are now down to zero kWh per day for electric hot water, and we are sending supplementary heat out to the passive solar porch and to the master bathroom. Oil consumption is also down significantly from the time, just a year ago, when we were dependent on our oil-fired boiler for our hot water. We expect additional oil savings due to the radiation of stored heat from the porch's cement slab to our bedroom, bath and solar porch areas.

We spent about $5,950 less in 2009-2010 than we would have spent if we were still using oil- and utility-provided electricity in the same amounts as in 2002-2003. If the current $2.83 per gallon price of heating oil and the current PSNH marginal rate of 15 cents per kilowatt-hour hold, we project that our annual savings will rise to about $6,400 in 2010-2011, as our new solar thermal system and other recent initiatives come fully on line. These savings will, of course, recur each year and will be fully protected from inevitable above-average inflation in energy prices. (From April 2002 through March 2010, when the general rate of inflation was 21.04 percent according to inflationdata.com, the price of heating oil for us went up by 146 percent, and the price of PSNH electricity went up by 39.8 percent.) Also, the savings are tax free. Had we not made our energy investments, we would need to earn at least $8,500 - before taxes - to produce $6,400, post-tax, for the purchase of that saved energy in 2010-2011.

I will not try to quantify the dollar value of our energy-related investments or the annual yield and the probable payback period on those investments. For one thing, I am not sure how to separate energy-related costs from remodeling or home improvement costs. I also don't know how to quantify the value of our sweat equity, as, over the years, I did all the demolition work and most of the renovation and installation work. Only the specialized parts of the plumbing, heating, electrical, concrete and active solar system work was left to skilled professionals. More importantly, however, energy-saving opportunities vary greatly from house to house, and the cost of responding to those challenges varies greatly from year to year. In short, our particular cost experience at our old and sprawling house does not generalize to other settings. What does generalize, however, is the potential, demonstrated by our particular experience, for huge energy savings.

The change in just these last two years in the cost of a PV solar system illustrates this point. Our experience demonstrates that PV systems work well in southwestern New Hampshire, producing a predictable amount of electricity each year and radically reducing net consumption of utility-provided electricity. But the cost of a PV system today is dramatically lower than when we installed. Prices of PV panels are down by about 50 percent. Efficiency of panels is up. A federal income tax credit set at 30 percent of installed cost was capped at $2,000 when we installed; today, it is no longer capped. And the state of New Hampshire currently offers a rebate at $3 per watt, up to $6,000, which didn't exist when we installed. And finally, a 5.1-kW PV system seemed right for our situation, but a smaller, less expensive PV system may be a better choice in other circumstances. So our PV investment cost experience is not relevant today, but our success in generating electricity and reducing our annual energy bill is.

Thus, each homeowner and each financing entity will need to make a particular financial and energy judgment. If unfamiliar with energy issues, an energy audit by a competent professional will often be a good place to start. The cost of targeted energy-related investments and the likely energy savings may then be projected. In most cases, as has been true for us, such a careful financial and energy assessment will usually demonstrate the economic viability of the indicated energy-related investments. Indeed, as in our case, the financial assessment is also likely to demonstrate the absence of any conservative alternative investment that will guarantee comparable yields with protection against energy inflation over the long term. (The fact that the energy investment will be relatively illiquid will need to be part of the assessment. Although the changes will almost certainly add long-term value to a property, market conditions at the time of any necessary sale of the property may prevent recovery of the energy investment.)

Even with better subsidies and dropping prices, most homeowners will not be able to self-finance. To realize the income-generating potential of energy investments in their homes, new financing vehicles are needed. Expanded government rebates and tax credits for energy-saving and renewable energy initiatives are helping to close the gap. This report, and other reports like it, may help bank loan officers, real estate brokers and appraisers, government officials, and others in the housing finance business understand that energy investments do produce economic returns that are sufficiently reliable to support market and below-market rate loans. Renewable energy leasing options, power purchase agreements, and municipal loan systems tied to the property tax are all good options for shifting some of the financing burden from homeowners. These and other initiatives that offer the prospect of bridging the existing financing gap should be supported.

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About the Author: Richard Ames is a retired attorney. Concerns about the perils of climate change, environmental degradation, fossil fuel dependency and resource inequality motivate his work on energy-use alternatives. He chairs the Town of Jaffrey Energy Committee.