by jboullion | Dec 18, 2009 | Uncategorized
By Michael Vickerman, RENEW Wisconsin
As a result of educating themselves on the connection between energy use and atmospheric pollution, several school districts in Wisconsin are taking increasingly aggressive steps to conserve energy as well as produce a portion of what they use on-site. Some have embraced ground source heat pump systems (Fond du Lac High School), while others have installed solar hot water systems (Osceola Middle School) and solar electric systems (Paul Olson elementary school in Madison). Not to be outdone, Wausau East High School recently installed a 100 kilowatt (kW) Northwind turbine, which is now the largest wind generator attached to a school building in Wisconsin.
Yet if one measures success by substantial reductions in energy expenditures and emissions reductions, there is one school district in Wisconsin that stands head and shoulders above its peers: Fort Atkinson. Serving 2,700 school-age children in a community of 12,000, the Fort Atkinson School District operates six buildings: four elementary schools, one middle school and a high school. School officials have made no secret of their aspiration to make Fort Atkinson the most energy-efficient and self-sufficient K-12 district in the state.
Since 2005, Fort Atkinson has rigorously pursued a sustainable energy agenda that integrates, in a systematic and complementary fashion, continuous monitoring of consumption, aggressive building efficiency measures, and renewable energy capture. As articulated in its 2009 energy plan, the district’s principal goals for 2010 are nothing if not ambitious:
Pare energy costs by 20% from 2005 levels;
Lower carbon emissions by 25% from 2005 levels;
Obtain EnergyStar certification for all six schools; and
Install on-site renewable production at all six schools.
Virtually every renewable energy technology or efficiency measure available to a Wisconsin K-12 district has already been or is about to be deployed somewhere in Fort Atkinson. This lengthy list includes ground source heat pumps, solar hot water systems, lighting retrofits, tankless water heaters, retro-commissioning, occupancy sensors, window replacement, and roof insulation. On the district’s 2010 installation list are a 50 kW wind generator at the high school and a 20 kW solar electric system at Purdy elementary school.
The integrated approach pursued by Fort Atkinson leads to lower operating expenses, which in turn frees up capital for renewable technologies that have higher up-front costs but will deliver energy to the school buildings long after the initial investment is paid off. At the same time, converting sunlight and wind into useful energy sources enable building owners to reduce the variability of their utility costs. For a school district, that means not having to worry about the effect of a colder-than-normal winter on next year’s budget for textbooks.
The solar water heating systems serving the high school and the middle school neatly illustrate this benefit. The radiant energy striking the rooftop panels year-round is efficiently collected and taken inside to preheat the swimming pools in each building. Except during the winter months, the incoming solar energy is sufficient to maintain pool temperatures at 84°F. Even in January, however, the savings that a solar hot water system yields simply by preheating a pool to 70°F is substantial when multiplied over several decades.
The capital required to heat a swimming pool with solar energy is not trivial. For the 48-panel system atop the high school, the installed cost totaled $192,000, while the 32-panel installation serving the middle school came in at $115,000. Dennis Kuchenmeister, who manages the district’s buildings and grounds, estimates a 5% return on investment (ROI) for the high school’s system and an 11% ROI on the middle school’s system. According to Kuchenmeister, the hot water systems will supply about 60% of the heat going into the pools, displacing the equivalent of nearly 9,000 therms a year. The district expects to save $18,000 in avoided fuel costs per year.
Kuchenmeister’s economic estimates factor in incentives from Focus on Energy covering up to 35% of the total installed cost and matching incentives from We Energies, the local utility serving the school district. By taking full advantage of available incentive dollars, the school district was able to reduce the out-of-pocket portion of installation costs by more than 50%.
Because the annual harvest of solar energy striking a particular spot rarely fluctuates by more than 10%, a building owner can be reasonably confident of how much conventional energy an installation will displace. In contrast, the cost of heating a pool with natural gas can easily triple during a 12-month period even when usage remains constant. This in fact happened to Fort Atkinson in the 12 months preceding the installation of its two solar hot water systems in the fall of 2008.
Thus, the real value of Fort Atkinson’s solar hot water installations is in minimizing the district’s exposure to the price volatility associated with unregulated fossil fuels like natural gas. And while it’s true that natural gas prices are presently at five-year lows, they could easily bounce back to 2008 levels in a year or two, depending on events over which end-users have no control. However, by installing a renewable technology that preheats their swimming pools, Fort Atkinson has effectively insured itself against a repeat appearance of the fossil fuel rollercoaster ride that most school districts would just as soon forget.
There are two other reasons why school buildings are well-matched for solar energy installations. First, the buildings themselves are dedicated to a public function that is expected to last for several generations. In such settings it is easier to justify the additional up-fronts costs, especially if the installation also communicates a valuable lesson in sustainability to the entire community. Second, most schools, especially newer ones, have an abundance of flat, unshaded roof space that can support large arrays, irrespective of building orientation.
Real-time production data from both installations can be accessed online by visiting www.fatspaniel.net and searching for the live sites listed under We Energies. The district also uses Energy Watchdog, a web-based program provided by Focus on Energy to track energy usage. This program enables Fort Atkinson to document the energy and cost reductions from measures specified in its energy plan.
The middle school is also one of four schools in Fort Atkinson equipped with ground source heat pump systems that heat and cool the buildings year-round using the nearly constant temperatures in the ground. These systems heat buildings in the winter and cool them in the summer. Ground source heat pump systems are electrically powered; no heating fuel like natural gas or propane is needed to heat the four schools.
“We essentially cut the gas line to our schools,” said Kuchenmeister during a presentation on his district’s sustainable energy initiative last November in Milwaukee.
The operational costs of ground source heat pumps are substantially lower than the HVAC systems they replace. As a result of their renovation, the three elementary schools have seen their energy intensity drop by more than one-half, even though they now have air-conditioning in the classrooms. School officials estimate that all four ground source heat pump systems will save the district $90,000 annually in fuel costs.
As with solar hot water systems, Focus on Energy provides incentives for ground source heat pumps to schools, businesses and residences. The program awarded more than $96,000 towards the four systems installed in Fort Atkinson.
According to a Focus on Energy fact sheet, “a ground source heat pump system is arguably the most efficient technology for heating and cooling Wisconsin homes and businesses.” Given its embrace of that technology and others deployed in its buildings, Fort Atkinson has become, in terms of energy sustainability, arguably the most forward-thinking school district in the state.
RENEW Wisconsin (www.renewwisconsin.org) is an independent, nonprofit 501(c)(3) organization based in Madison that acts as a catalyst to advance a sustainable energy future through public policy and private sector initiatives. Michael Vickerman has been the organization’s executive director since 1991.
Solar Hot Water Systems – Fact Sheet
Fort Atkinson School District
Full Service Installers
Andy DeRocher
Mark O’Neal
Full Spectrum Solar
100 South Baldwin Street, Suite 101
Madison, WI 53703
Phone: 608.284.9495
info@fullspectrumsolar.com
www.fullspectrumsolar.com
Types of system installations:
Solar hot water, solar electric
Service Territory:
150 miles
At-A-Glance – High School SHW System
Collector space: 1,920 sq. ft (48 4’x10′ panels)
Panel manufacturer: Heliodyne Gobi
Tilt angle: 45 degrees
Annual fuel savings: 8,539 therms assuming 80% efficient gas boilers
Avoided CO2 emissions: 47 tons/year
Pool Size: 4,200 sq. ft.
Preheated water volume: 188,227 gallons
Pool operating temperature: 80°F
Incoming water temperature: 55°F
Installation cost: $192,000
Focus on Energy Incentive: $50,000
We Energies match: $50,000
System payback: 10 ¾ years
Installation date: Fall 2008
At-A-Glance – Middle School SHW System
Collector space: 1,280 sq. ft (32 4’x10′ panels)
Panel manufacturer: Heliodyne Gobi
Tilt angle: 45 degrees
Annual fuel savings: 8,763 therms assuming 60% efficient gas boiler
Avoided CO2 emissions: 49 tons/year
Pool Size: 2,635 sq. ft.
Preheated water volume: 96,921 gallons
Pool operating temperature: 84°F
Incoming water temperature: 55°F
Installation cost: $115,000
Focus on Energy Incentive: $40,400
We Energies match: $40,400
System payback: 4 years
Installation date: Fall 2008
by jboullion | Dec 15, 2009 | Uncategorized
IMMEDIATE RELEASE
December 15, 2009
MORE INFORMATION
Michael Vickerman
RENEW Wisconsin
608.255.4044
mvickerman@renewwisconsin.org
Report: Wind Turbines Cause No Human Harm
Consistent with 10-plus years of commercial wind generation operations in Wisconsin, a national report issued today concluded that the sounds produced by wind turbines are not harmful to human health, according to the state’s leading renewable energy advocacy group.
Comprised of medical doctors, audiologists, and acoustical professionals from the United States, Canada, Denmark, and the United Kingdom, the panel of reviewers undertook extensive analysis and discussion of the large body of peer-reviewed literature, specifically with regard to sound coming from wind turbines.
The panel was established by the American Wind Energy Association and the Canadian Wind Energy Association (CanWEA).
“This report corroborates testimony that RENEW presented in the ongoing Glacier Hills Wind Park hearings at the Wisconsin Public Service Commission,” according to Michael Vickerman, executive director of RENEW Wisconsin. In that proceeding, We Energies is seeking approval to construct a 90-turbine 162 megawatt wind park in northeast Columbia County.
“If there were a human health impact with wind generation, why are communities such as Rosiere in Kewaunee County and Montfort in Iowa County so supportive of the wind installations nearby?” commented Vickerman.
“The experience suggests that nearby residents gradually overcome any initial misgivings and accept the turbines for what they are: clean, visible, and environmentally benign producers of renewable energy,” he continued.
According to Dr. Robert J. McCunney, one of the authors of the national multi-disciplinary study and an occupational/environmental medicine physician and research scientist at the Massachusetts Institute of Technology (MIT), “There is no evidence that the sounds, nor the sub-audible vibrations, emitted by wind turbines have any direct adverse physiological effects on humans.”
Another member of the panel, Dr. Geoff Leventhall, an acoustical consultant on sound and health for more than 40 years, testified during recent regulatory proceedings on the proposed 162 megawatt Glacier Hills Wind Park in Columbia County.
“Attempts to claim that illnesses result from inaudible wind turbine noise do not stand up to simple analyses of the very low forces and pressures produced by the sound from wind turbines,” said Leventhall in sworn testimony.
The national study’s top findings include:
• “The sounds emitted by wind turbines are not unique. There is no reason to believe, based on the levels and frequencies of the sounds, that they could plausibly have direct adverse physiological effects.”
• If sound levels from wind turbines were harmful, it would be impossible to live in a city given the sound levels normally present in urban environments.
• “Sub-audible, low frequency sound and infrasound from wind turbines do not present a risk to human health.”
• “Some people may be annoyed at the presence of sound from wind turbines. Annoyance is not a pathological entity.”
An executive summary of the report can be accessed here (PDF, 81KB). The full report can be accessed here (PDF, 440KB).
by jboullion | Dec 7, 2009 | Uncategorized
The solar water heating systems serve Fort Atkinson high school and the middle school. The radiant energy striking the rooftop panels year-round is efficiently collected and taken inside to preheat the swimming pools inside each structure. Except during the winter months, the incoming solar energy is sufficient to maintain pool temperatures at 84°F. Even in January, however, the savings that a solar hot water system yields simply by preheating a pool to 70°F is substantial when multiplied over several decades.
As a result of educating themselves on the connection between energy use and atmospheric pollution, several school districts in Wisconsin are taking increasingly aggressive steps to conserve energy as well as produce a portion of what they use on-site. Some have embraced ground source heat pump systems (Fond du Lac High School), while others have installed solar hot water systems (Osceola Middle School) and solar electric systems (Paul Olson elementary school in Madison). Not to be outdone, Wausau East High School recently installed a 100 kW Northwind turbine, which is now the largest wind generator attached to a school building in Wisconsin.
Yet if one measures success by substantial reductions in energy expenditures and emissions reductions, there is one school district in Wisconsin that stands head and shoulders above its peers: Fort Atkinson. Serving 2,700 school-age children in a community of 12,000, the Fort Atkinson School District operates six buildings: four elementary schools, one middle school and a high school. School officials have made no secret of their aspiration to make Fort Atkinson the most energy-efficient and self-sufficient K-12 district in the state.
Since 2005, Fort Atkinson has rigorously pursued a sustainable energy agenda that integrates, in a systematic and complementary fashion, continuous monitoring of consumption, aggressive building efficiency measures, and renewable energy capture. As articulated in its 2009 energy plan, the district, the district’s principal goals for 2010 are nothing if not ambitious:
+ Pare energy costs by 20% from 2005 levels;
+ Lower carbon emissions by 25% from 2005 levels;
+ Obtain EnergyStar certification for all six schools; and
+ Install on-site renewable production at all six schools.
Virtually every renewable energy technology or efficiency measure available to a Wisconsin K-12 district has already been or is about to be deployed somewhere in Fort Atkinson. This lengthy list includes ground source heat pumps, solar hot water systems, lighting retrofits, tankless water heaters, retro-commissioning, occupancy sensors, window replacement, and roof insulation. The most recent system to be installed, a 50 kilowatt wind turbine at the high school, will be operational by Christmas 2009.
The integrated approach pursued by Fort Atkinson leads to lower operating expenses, which in turn frees up capital for renewable technologies that have higher up-front costs but will deliver energy to the school buildings long after the initial investment is paid off. At the same time, converting sunlight and wind into useful energy sources enable building owners to reduce the variability of their utility costs. For a school district, that means not having to worry about the effect of a colder-than-normal winter on next year’s budget for textbooks.
The solar water heating systems serving the high school and the middle school neatly illustrate this benefit. The radiant energy striking the rooftop panels year-round is efficiently collected and taken inside to preheat the swimming pools inside each structure. Except during the winter months, the incoming solar energy is sufficient to maintain pool temperatures at 84°F. Even in January, however, the savings that a solar hot water system yields simply by preheating a pool to 70°F is substantial when multiplied over several decades.
The capital required to heat a swimming pool with solar energy is not trivial. For the 48-panel system atop the high school, the installed cost totaled $198,000, while the 32-panel installation serving the middle school came in at $115,000. Dennis Kuchenmeister, who manages the district’s buildings and grounds, estimates a 5% return on investment (ROI) for the high school’s system and an 11% ROI on the middle school’s system. According to Kuchenmeister, the hot water systems will supply about 60% of the heat going into the pools, displacing the equivalent of nearly 9,000 therms a year. The district expects to save $18,000 in avoided fuel costs per year.
Kuchenmeister’s economic estimates factor in incentives from Focus on Energy covering up to 35% of the total installed cost and matching incentives from We Energies, the local utility serving the school district. By taking full advantage of available incentive dollars, the school district was able to reduce the out-of-pocket portion of installation costs by more than 50%.
Because the annual harvest of solar energy striking a particular spot rarely fluctuates by more than 10%, a building owner can be reasonably confident of how much conventional energy an installation will displace. In contrast, the cost of heating a pool with natural gas can easily triple during a 12-month period even when usage remains constant. This in fact happened to Fort Atkinson in the 12 months preceding the installation of its two solar hot water systems in the fall of 2008.
Thus, the real value of Fort Atkinson’s solar hot water installations is in minimizing the district’s exposure to the price volatility associated with unregulated fossil fuels like natural gas. And while it’s true that natural gas prices are presently at five-year lows, they could easily bounce back to 2008 levels in a year or two, depending on events over which end-users have no control. However, by installing a renewable technology that preheats their swimming pools, the Fort Atkinson has effectively insured itself against a repeat appearance of the fossil fuel rollercoaster ride that most school districts would just as soon forget.
There are two other reasons why school buildings are well-matched for solar energy installations. First, the buildings themselves are dedicated to a public function that is expected to last for several generations. In such settings it is easier to justify the additional up-fronts costs, especially if the installation also communicates a valuable lesson in sustainability to the entire community. Second, most schools, especially newer ones, have an abundance of flat, unshaded roof space that can support large arrays, irrespective of building orientation.
Real-time production data from both installations can be accessed online by visiting www.fatspaniel.net and searching for the live sites listed under We Energies. The district also uses Energy Watchdog, a web-based program provided by Focus on Energy to track energy usage. This program enables Fort Atkinson to document the energy and cost reductions from measures specified in its energy plan.
The middle school is also one of four schools in Fort Atkinson equipped with ground source heat pump systems that heat and cool the buildings year-round using the nearly constant temperatures in the ground. These systems heat buildings in the winter and cool them in the summer. Ground source heat pump systems are electrically powered; no heating fuel like natural gas or propane is needed to heat the four schools.
“We essentially cut the gas line to our schools,” said Kuchenmeister during a presentation on his district’s sustainable energy initiative last November in Milwaukee.
The operational costs of ground source heat pumps are substantially lower than the HVAC systems they replace. As a result of their renovation, the three elementary schools have seen their energy intensity drop by more than one-half, even though they now have air-conditioning in the classrooms. School officials estimate that all four ground source heat pump systems will save the district $30,000 annually in fuel costs.
As with solar hot water systems, Focus on Energy provides incentives for ground source heat pumps to schools, businesses and residences. The program awarded more than $96,000 towards the four systems installed in Fort Atkinson.
According to a Focus on Energy fact sheet, “a ground source heat pump system is arguably the most efficient technology for heating and cooling Wisconsin homes and businesses.” Given its embrace of that technology and others deployed in its buildings, Fort Atkinson has become, in terms of energy sustainability, arguably the most forward-thinking school district in the state.
by jboullion | Nov 20, 2009 | Uncategorized
From a fact sheet issued by the Homegrown Renewable Energy Campaign:
An innovative way to encourage more smaller-scale renewable energy systems by paying premiums to customers for wind, solar, biogas or biomass electric generation.
How are they different from standard utility buyback rates?
Unlike standard buyback rates, Renewable Energy Buyback Rates provide a fixed purchase price for the electricity produced over a period of 10 to 20 years. They are set at levels sufficient to fully recover installation costs along with a modest profit. Because the purchase price is guaranteed over a long period, Renewable Energy Buyback Rates make it easy for customers to obtain financing for their generation projects.
Why don’t utilities pursue these small-scale renewable projects themselves?
In general, the smaller the generating facility, the less likely it is owned by a utility. Utilities tend to favor bulk generation facilities that employ economies of scale to produce electricity at a lower cost. Renewable power plants owned by
utilities—such as large wind projects—are sized to serve their entire territory, not just a particular distribution area. For that reason utilities have shown little appetite for owning and operating distributed generation facilities powered with
solar, biogas, wind, and hydro.
If utilities won’t invest in small-scale renewable projects, how will they get built?
Clearly, the capital needed to build smaller-scale renewable projects has to come from independent sources—either customers or third parties. There is no shortage of investor interest in these systems, and sufficient capital is available. What’s needed to finance these projects is a predictable, long-term purchasing arrangement that assures full capital recovery if the project performs according to expectations. That’s where Renewable Energy Payments come into play.
by jboullion | Nov 12, 2009 | Uncategorized
The Koerner’s installed the domestic hot water system (right)in March 2006. It also provides a portion of the heat for the house.
Sun Harvest Farm, owned by Jerry and Penny Kroener, Ridgeway, WI
Renewable Energy Projects
September 2009 Update
General:
In 2005 we embarked on major renovations and additions to our old farmhouse. This included working with Focus on Energy to have site assessments performed for Solar Photovoltaic, Solar Thermal and Wind Turbine Systems. We also investigated wood burning systems because we have substantial quantities of firewood on our property. Our decisions included the following:
1. Add additional insulation, all new windows and new doors.
2. Replace our old oil burning furnace with a high efficiency propane boiler (our little Munchkin).
3. Install a Solar Photovoltaic grid-connected system to produce electricity.
4. Install a Solar Thermal (hot water) system to preheat domestic hot water and provide some house heat.
5. Install a counter-flow masonry heater fireplace using our own limestone for the masonry cladding.
6. In 2008 we built and installed a hot air collector to provide some heat in our barn workshop.
7. In 2009 we installed our 2nd Photovoltaic grid-connected system.
8. In 2009 we also upgraded our solar hot water storage tank.
Improving Efficiency
Our first goal was to improve the efficiency of the areas in the old part of the farmhouse, and to include very high efficiency within the new addition. We installed new Pella windows and doors throughout. Additional insulation was added where possible and a moisture/air barrier under new fiber cement siding, which was installed on the entire house. The new construction included R-21 insulation in the walls and blown-in R-50 in the ceiling. We removed the old oil-fired hot water heater and the oil burner from the warm air furnace. A high efficiency propane gas boiler (Munchkin T-50) was installed to be our back up for heating and the new domestic hot water tank. We also installed radiant under floor heating in the new great room area and plan to install additional radiant heating in certain of the old house areas. The existing warm air furnace was retained, with the addition of a water-to-air heat exchanger, which allowed us keep the central AC unit and also to provide warm air heating to the upstairs area. We have also installed compact fluorescent light bulbs throughout the entire house and in the barn workshop area.
Solar Thermal Hot Water System
Our system as designed to provide domestic hot water and a portion of the house heating and was put into operation in March 2006. It includes:
+ Eight 4 ft x 10 ft Heliodyne Gobi 410 collectors, ground-mounted at a 60 degree tilt angle
+ 1000 gallon concrete hot water storage tank, with EPDM rubber liner
+ Approximately 600 ft of 1 inch copper tubing made into coils for heat exchangers
+ Pump, valves, expansion tanks, controller, copper piping, propylene glycol, insulation, etc.
We performed a considerable amount of the work to install the system including:
+ Installing the concrete tank and liner
+ Bending the tubing into coils and installing them in the tank
+ Installing 14 concrete pillars
+ Digging trenches and installing piping from collectors into basement
+ Erecting the framework and the collectors
We worked with Light Energy Systems of Madison (now Full Spectrum Solar) to design the system and to provide the parts and some of the labor. The total system cost was approximately $20,000, but we received a Focus on Energy grant of $3,000 and a Federal Tax Credit of $2,000 so our out-of-pocket costs were about $15,000.
During 2009 we decided to replace the concrete tank due to excessive moisture problems in the basement area. We demolished the tank piece by piece and carried it out of the basement. We replaced it with a tank made by STSS Co. Inc from Mechanicsburg PA. The new tank is collapsible so it can be moved through regular sized doorways. When in place it will be 80 round and 4 high with all penetrations installed at the factory according to our heat exchanger specifications. It is sealed, insulated and with hold up to 822 gallons of water. We reused the copper heat exchangers that we had made for the old tank. We also installed a heat dump under the solar collectors, which was made of 24 ft of Slant Fin baseboard hydronic registers. The purpose of the heat dump is to dissipate excess heat produced during the summer when we only use the hot water for pre-heating the domestic hot water. The total costs for the new tank, including demolishing the old tank, were about $3,500.
Masonry Heater Fireplace
We investigated wood-burning systems and decided to build a masonry heater fireplace in order to take advantage of renewable resources on our property. We have an ample supply of trees on our property that we harvest by cutting dead trees. We constructed a woodshed that dries and stores about 10 cords of split firewood.
The fireplace is specially designed to be efficient and environmentally friendly because the combustion chamber burns at between 1500-2000 degrees F. The fire burns for 2-3 hours but the large amount of masonry mass stores and radiates the heat for 12-24 hours. Our fireplace is centrally located so it radiates heat over a large area of our kitchen and great room. Two stainless steel U-Tube heat exchangers are also built into the core to capture some heat, which is circulated to the solar storage tank in the basement.
The core of our heater was designed by Heat-Kit of Canada, but originated centuries ago from designs in Europe and Russia. Gimme Shelter Construction of Amherst, WI constructed the core.
We decided to use natural limestone and sandstone from our property for the masonry cladding. Some of the stones were recovered from the foundation of our old summer kitchen. We performed the masonry work ourselves, which saved us $20,000+ in labor costs. Our cost for the core, chimney materials and mortar for the limestone was approximately $12,000.
Solar Photovoltaic Electric System # 1
This system was designed to produce about half of our annual electricity needs and was put into operation in April 2006. We chose a grid-tied system that sends excess electricity to the Alliant Energy power grid. We have a net-metering agreement where we are compensated for the power we produce at the same rate as we pay for electricity. During the first full year of operation our PV system produced 4,700 kilowatt-hours, which was 43% of our total usage of 11,100 kWh.
The PV system includes the following components:
+ 16 Kyocera 170 watt modules for a total output of 2.7 kW
+ Wattsun dual axis tracker system (the system follows the sun morning until night)
+ SMA Sunny Boy 2500 inverter/controller (converts DC voltage to AC for the grid)
+ Concrete foundation (5 yds with rebar), steel post & framework
+ Disconnect switches, wires, conduit, and other miscellaneous electrical items
Our system produces between 200-600 volts (DC current) when the sun shines. It is facing east when the sun rises and follows the sun all day so it is facing west when the sun goes down. The DC current comes into the basement, goes through a disconnect switch and into the Sunny Boy inverter/controller. This device changes the DC current into AC current and controls how the power goes out into the grid. The current goes outside through a disconnect switch, back through our main breaker panel, and then out through the meter to the grid. The best days are when we are not using much power and the meter is actually going backward!
We worked with Light Energy Systems of Madison (now Full Spectrum Solar) to design the system and to provide the parts and some of the labor.
The total cost of the system was about $25,000, but we received a Focus on Energy grant of $8,700 and a Federal Tax Credit of $2,000, so out out-of-pocket costs were about $14,000.
Solar Photovoltaic Electric System # 2
In 2009 we installed our second PV system. We took advantage of a special program from Alliant Energy where we have contracted for 10 years to sell all of the power produced by the system for 25 cents per kWh. It did require us to install a new meter pedestal, at a cost of $1,100 so that the electricity from the new system could be metered separately. We also have to pay about 41 cents/day for the new meter charge, as well as sign up for the Alliant Second Nature program (where we pay a small premium for our energy purchased, which will be from renewable sources). Our total cost for the system was $31,168, and we did some of the work ourselves (digging, concrete, trenching, wire, etc). We will get a 25% Focus on Energy grant of about $7,800 and a 30% Federal tax credit in 2010 of about $9,300. Therefore, our out of pocket costs will be about $14,000. This system has the potential to produce about an 11% annual rate of return.
We purchased the main part of the system from DH Solar. Their system uses a tracking system that they adapted from their experience with commercial satellite tracking systems. The system has 16 Suncast PV panels, each of which is rated at 210 watts, or a total of 3.36 kW. The inverter is a SMA Sunny Boy 3000US.
Barn Workshop Hot Air Collector System
In 2008 we designed, built and installed a hot air collector system on the south side of the old milkhouse. The collector was made from tempered glass, aluminum expandable tubes, painted black, and solid foil-faced insulation. The 6 outlet and inlet piping contains a bi-metallic sensor/control relay and a small in-duct fan to pipe the heat into the barn workshop. The total cost of this system was about $600. A woodstove in the milk house provides backup heat on cloudy days, which is piped with the same piping system into the barn. This is a trial and error system. It looks like we might have to reposition the system to more directly face south to maximize the heat output.
