12.06.2016

Solar Power is Coming to the MMC


by Jeff Hawkins

In the fall of 2006 it became clear to the Conservation Committee that we were in the age of climate change and the Mazamas’ Mission to protect the mountain environment assumed a new urgency. We needed to do more. We needed direct links between our mission and our own actions. This led us to a vision for reducing the Mazamas carbon footprint. The committee first calculated the Mazamas’ carbon footprint, which mostly consists of emissions from automotive miles driven to our various activities, followed by the MMC and the lodge utilities—electricity, natural gas, and heating oil. Then in spring 2007 we created and hosted the Melting Mountains Conference for a packed house in the MMC. Glaciologist Andrew Fountain spoke along with political leaders from the City of Portland, Metro, and the Oregon Legislature. In the fall of 2009 we started a tree planting program and have worked in the Sandy Basin Watershed nearly every spring and fall for eight years planting an estimated 6,500 trees. There have been small efforts too, like installing a hand dryer in the restroom at the MMC to reduce a huge consumption of paper towels.

The next action is to install a solar electric array on the MMC. We tried once in 2008, but ran into legal issues and an economic recession that prevented us from obtaining financing. There were also important concerns about penetrating the MMC roof for attachment.

Things have changed. Installers now have available non-penetrating clamps for panel attachment to the seams of the MMC roof. Costs have come down by a factor of four. And there is better understanding on how to structure financing that works for non-profits.


Here are some basic parts of the plan:


  • A Power Purchase Agreement (PPA) is the legal structure we will be using to fund the array. It forms a relationship between an owner (Elemental energy) and a host (Mazama MMC). The owner finances the array. The host has the array on their building and purchases the power from the owner. This is an especially beneficial arrangement for the Mazamas. It allows us to work with a for-profit partner who can take advantage of the Federal Investment Tax Credit which is 43% of the funding.
  • PPAs come in variations. We will be using a prepaid PPA where the value of power to be generated over the duration of the contract is estimated and is paid up front. This is less complicated than making quarterly payments based on actual power generated and is significantly less costly due to eliminating administration—meter reading, billing, power payments and loan repayment to investors.
  • The Mazamas Foundation will be providing a loan to the Mazamas for the power pre-payment.
  • The array will generate ~41.4 kWh/year, which is estimated as 60 percent of the MMC’s electricity usage and is worth $4,300/year. The Mazamas will pay off the Foundation loan with these savings.
  • Elemental Energy, our for-profit partner (also the installer), will own the array for 10 years at which point the Mazamas will purchase the array at fair market value.

There are other costs:


  • We owe the Oregon Clean Power Coop $2,696 for developing the PPA contract and for arranging a for-profit partner. This will be loaned to the Mazamas by the Foundation.
  • Legal review of the PPA has been done and paid for from the Mazamas general spending account.
  • Installation of safety anchors, structural improvement, gutter repair, roof cleaning and tree removal are estimated to cost $10,000. This will be paid for by member contributions and the MMC maintenance account.
  • End of contract purchase is currently estimated at $2,538.

The solar array will be grid tied, that is, it will produce power only when the electrical grid is operating. There will be no batteries. We will not be able to power the MMC when PGE’s grid is down.

PGE will be our virtual battery. Excess power generated during the peak months of March through August will be “stored” as credits for use during the winter months when generation is lower and heating cost is higher. See illustration.

In every project there are concerns. These are the most commonly expressed and our responses,



    • Roof life: Two independent roof inspections indicate that the MMC roof is in excellent condition with an estimated life of 25 years or longer.

    • Roof attachment: We will be using a clamp that is designed to attach to the standing seam on the roof without penetration.

    • Roof strength: The roof is secured to the building along the seams with one screw every two feet. This is standard, but our roof inspector believes it is insufficient to safely support the weight of the array. We are seeking input from structural engineers that might lead us to add more screws at the top of each roof panel. Other roof work will be done at the same time—cleaning, repairing gutters, and adding safety anchors for array installation and future maintenance. 
    • Building strength: The trusses are on 24-inch spacing and in this situation the City of Portland does not require structural engineering. We have elected to do this anyway. Though when we had this done in 2008 the building was found to be more than strong enough for the then proposed 20 kW array that was only 60 percent the size of the current 37.4 kW array.
    • Legal issues: The PPA that will be in place between Mazamas and Elemental Energy was reviewed on behalf of the Mazamas by David Van’t Hof, an attorney who focuses on sustainability, clean technology, renewable energy and carbon regulation. David is also a Mazama member.
    • Contractor experience: Elemental Energy has been in business since 2008 and has installed nearly 300 hundred in Oregon and internationally. The have used this clamping system before. 
    • Should anything go wrong, in spite of our best efforts, the Mazamas Foundation will have insurance for damage to the structure and for the replacement value of the array.
    The next steps are to sign contracts, complete the detailed design of the array, submit plans to PGE for pre-approval, order materials, and complete installation by the end of February.

    Many thanks to many people for the participation and support along the way.

    • A long list of people in 2008 who contributed so much during the first attempt. You all know who you are.
    • Dan Orzech at Oregon Clean Power Coop for creating the current contracts and identifying our financial partner.
    • David Van’t Hof for legal review.
    • The Foundation Committee for detailed review of the contract, asking all the important questions and providing the loan to the Mazamas.
    • Bob Breivogel, John Rettig, Dan Crisp, Gerry Itkin and Jeff Hawkins for member financial contributions

    Come March your MMC will begin producing half of its annual power usage for the next 25 years—$4,300/year and approximately $130,000 total. And perhaps more importantly, we will be actively living the values we hold dear by protecting the environment we all cherish.

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