Heating Season Begins…

October 11, 2010

As we slide into the heating season again, it’s a great time to look at the energy usage in your home. Will it be the same as last year or are you looking to make some changes to add efficiency and reduce costs? As part of our GreenBridge/Riverview Builders design and construction services, we want to offer our clients alternative energy (wind, solar, geothermal) analysis and options as part of their building projects.

We looked to Adros Energy to be our collaborator for those clients interested in pursuing alternative energy options for their properties. Adros Energy is a company that offers engineered analysis of different alternative energy systems and weatherization for a given property. They work hard to keep up to date on current products and technologies, including geothermal, water, solar and wind. I’ve known Oliver Sheridan, their local regional representative, for years and was excited to hear about his joining Adros. To see how the collaboration might work, I decided to ask Oliver to visit, using me and my house as a model client and project. As a follow up, I hoped that my sharing my experience might give insight to the process and open up options for others for their own homes.

Our House

DSC01820 Winter 2009

We live in a house built in 1796 – it has a granite rubble foundation with the original structure and no wall insulation. We have a 10 year old oil-burning boiler and are hoping to install a high-efficiency gas unit this season. Our hot water is currently heated with gas.

To get the greatest benefit from any alternative energy system, weatherization, or ‘buttoning up’ of the house should be taken care of first. We’ve made some progress in that regard; Two years ago, we used the Green Cocoon to install soy-based insulation in the roof framing and at the connection of the 1st floor framing and the outside wall (the band joist). These are high-payback locations and in our house, were also the most accessible. Our heating and cooling have been reduced by about a third. We still have weatherization ‘issues’, but also want to take advantage of tax and rebate incentives while they are still available.

The Assessment

Because we have already had an audit done and have a good understanding of our weatherization needs, Oliver limited his review to alternative energy options. We were primarily interested in solar hot water heat and although pricey, we also wanted to learn about the opportunities for a photovoltaic (PV) system for the future.

Oliver came with the solar orientation of the house in hand, so he knew that we have a pretty good roof for solar. It’s a hip roof, with one of the long sides facing predominantly south. Oliver usually takes enough measurements to be able to estimate the space available and to roughly design a system, but I had drawings and measurements he could use.

He came last week, on what was (I think) our last hot muggy day of the year. I gave him a tour of the house ending in the basement, which was stuffy and muggy as usual. He noticed our dehumidifier and suggested that we consider an Air to Air Heat Pump instead of a solar hot water system for our water-heating needs. A less expensive system up-front, it pulls the heat from the air around it and uses it to pre-heat water before it goes to the water heater. Extracting heat from our basement is an advantage since it provides free air conditioning and dehumidification–because it cools air as it is circulated through the heat pump. For us, Oliver suggested it as a more affordable solution that would help us with our humid basement.

Alternative Energy Options and Proposals

Oliver followed up with proposals and analyses for a 2.3 kW photovoltaic system on the roof, an air to air heat pump water heater, made by Geyser, and a solar hot water heater option.

Photovoltaic system

image

Schematic layout of a PVC system for our home

The photovoltaic array proposed by Oliver and Adros would generate 2,500 kwh annually.

Besides saving us money on our electrical bill, the proposed system would also enable us to earn money by selling solar renewable energy credits (SREC’s) from the kWh’s the system produces. In MA it is predicted that we could get anywhere from .20 to .40 cents per kWh. Using the lower end of that range, .20 cents per kwh, our system would earn an additional $500 annually. This SREC program is in place until the year 2025.

The Adros proposal includes installation with all necessary components and labor for a completely operational system including all electrical work needed and manage the connection to the grid.

Costs and Incentives:

PV array components, installation and wiring      $13,400

Total Financial Incentives*                                          -($6,320)

Cost after Financial Incentives                              $7,080

*  Financial Incentive Summary: Federal Income Tax Credit (30% PV) of $4,020 + MA CEC Rebate $1.00/watt $2,300 =Total Financial Incentives of $6,320)

Using Oliver’s estimates for savings and the SREC’s, based on current energy prices, we’d save $925 annually. The system would be paid for in approximately 7 years.

Air to Air Heat Pump Water Heater option:

installation diagram

The Geyser system illustrated

This price is for parts and labor for a turnkey installation of a fully operational unit.

Costs and Incentives:

Geyser Heat Pump, supplied and installed                   $2,900

30% Federal income tax credit                                       –($870)

Total after incentives                                                   $2,030

Annually, Adros projects a savings of $147 annually from the current gas-fired hot water heater cost, and $200 for the cost of the electrical dehumidifier, for a total savings of $347 annually. The system would be paid for in around 6 years.

Solar hot water heater option:

image

solar collectors on a roof

The pricing includes a complete system with all necessary equipment including solar collectors, roof mounting system, collector connections pipes, pump station, system controller and storage tank, all installation labor, plumbing work and electrician work. The system uses flat plate solar collectors with an 80 gallon storage tank (sized for 2-4 people).

Costs and Incentives:

System Costs                                                                          $11,200

Total incentives  **                                                                -($4,110)

Total after incentives                                                     $7,090

** Financial Incentive Summary: Federal Income Tax Rebate of $3,360 + Federal Solar Hot Water Tax Credit $750 = Total Financial Incentives of $4,110

Adros projects a savings of approximately $240 annually (at current fuel prices), so system would be paid for after 29 years!

Our plans:

Each year, we hope to increase the efficiencies of our home and its use of renewable resources to meet our energy needs. Based on these proposals and projections by Adros, we are most excited about the heat pump. We also really want to make the move on the PV system, and can’t wait to see solar panels on this 1796 roof, but will need to assess our home improvement budget for this year.

For more information on alternative energy options, feel free to contact me or Oliver at Adros Energy. ollie.sheridan@adrosenergy.com. You can also see the Adros website for more information. www.adrosenergy.com

Happy heating season!

Juli  juli@greenbridgearchitects.com

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One Response to “Heating Season Begins…”

  1. greenbridge Says:

    Thanks for the comment…how much are the portable a/c units these days? What is their efficiency compared to window units? J


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