White Mountain Energy Project (WMEP)

The goal of the White Mountain Energy Project is to improve energy quality and reliability, increase safety, reduce costs, and test innovative technologies at WMRC field stations.


Inverter system in Barcroft Energy Lab, in its 4th year of operation. The two grey units on left are 5000 watt "Sunny Boy" inverters, not currently in use. The four black units are "Outback VFX3648" inverters which are slaved together to invert 14.4 kW of electricity from a 48 volt battery bank (foreground in green, in insulated box). The two black units mounted on the right of the Outback inverters are Outback MX charge controllers which convert the output of the rooftop solar panels to charge the batteries. The black box raised above the other units contains a balancing transformer to balance the two legs of the 240 V current. The grey boxes contain breakers switches and other components. The raised water container is part of the battery watering system. When not in use, it is stored in the insulated box along with the batteries to prevent freezing. System schematic showing details of components. Click on photo to enlarge.

November 2, 2011 update. The WMEP solar/inverter/battery system worked flawlessly during 2011. Diesel generator run time was minimal, averaging only an hour or two per day: about 200 gallons of diesel fuel for the year. The generator was needed only when the number of visitors exceeded 4-6, or bad weather reduced solar energy output. The hydronic heating system boilers consumed between 750 and 1000 gallons of propane for the entire year, with a three year running average of 800 gallons per year. We also burned about 225 gallons of propane to operate the domestic hot water heater and the kitchen . This is remarkable efficiency for a facility that totals 12,000 square feet and supports a live-in staff as well as five hundred visitor-nights per year and a flock of 80-90 sheep. Much of the credit for this success goes to the station staff, who have optimized its performance as well as effectively training visitors in energy conservation. We have now set the system to run about 500 watts continuously through the winter, with no planned servicing until next June. The critical loads power system (see details below) operated in 2011 with no problems and continues to power certain critical communications links.

April 28, 2011 update. Last November we set the Barcroft inverter system to run about 500 continuous watts of computers, communication devices, and a battery charger for the microturbine generator. We also set the charging parameters for the Outback MX solar chargers to "sealed battery" specifications in order to conserve water ("bulk absorb" = 57.6 V, "float" = 53.6V). The system worked continuously all winter, with no damage to any of the solar panels. On April 28 we were able to hike up to Barcroft and check the system, adding water to the batteries for the first time in 4 1/2 months. The batteries (totalling 48 cells) took only 7 1/4 gallons of water, or 0.57 liters (2 1/2 cups) per cell. This suggests the possibility of running the system "maintenance-free" though the 6-7 month off-season when access is blocked by snow.

Barcroft update, November 15, 2010. Last summer we made a full recovery from the wind damage to the system, and by September were operating nearly 100% on the solar battery system. The battery bank seemed to have made a full recovery, and the panels are operating at 80-90% of their former capacity.


The roof panel repairs (see photo above taken in December 2010 after winter shutdown of the station) were carried out as follows: We divided each 6-panel sheet into 2 sheets of three for easier handling. We straightened, cleaned and tested each sheet on a long table made of plywood and sawhorses, and then re-attached the panels to the roof. Three types of EPDM adhesive were used, 3" wide EPDM doublestick tape, EPDM/TPO surface primer, and EPDM LC-60 bonding adhesive. We used the tape to bond and align the upper edge of each 4' wide EPDM sheet, and then rolled the sheet up onto the top of the roof. We coated the roof and underside of the sheet with primer and then applied the adhesive to the roof. We then unrolled the sheet onto the roof and sealed it by carefully walking over the panels and sheet. This required use of a climbing harness to safely work on the steep parts of the roof. We also applied clear silicone caulking to the upper surface of the panels where damage may have occured: this is to keep water out and prevent further deterioration.


In October 2010 we installed a new "critical loads" power system independent of the main power system. It consists of 4 rooftop solar panels, a "Tristar" MPPT charge controller (white with black top in photo), a Morningstar 300W inverter (black), and 22 used gel batteries. The battery housing was not completed before snow closed the station in October. The batteries were donated by the UC Riverside Magnetotellurics Imaging Project based at OVL. The purpose of this independent power system is to ensure active telecommunications and monitoring even when the main power system shuts down to protect itself.

See earlier 2010 news stories

2009: Snowstorm ends season before completion of monitoring and controls system! Will continue work in June 2010. see rest of story

2009: Three sets of solar panels blown off Quonset roof: seem to be OK! see rest of story.

2009: We made two trips to Barcroft in January see rest of story.

Other news stories:

Resource Diagrams and Documents

The original team: L to R John Smiley, Jim Maclay, Ryan Gaylord, Phil Pister, Scott Samuelsen. Jim Meacham not present.