Resource Conservation Program Summary Report
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Resource Conservation Program Summary Report Prepared By Chris Bruno Resource Conservation Manager December 2015 Issaquah School District Resource Conservation Program Summary The Resource Conservation Program began in September 2000 for management of energy/water usage, garbage reduction, commingled recycling and compostable recycling. The aim of the program is to reduce utility costs and consumption of resources but to meet and sustain those goals, continuous monitoring and education are required. Below are the year’s highlights compared with historical data. Detailed analyses are presented for each category. Combined Energy (MBtu) Usage of 126,903 about 7% decrease from the previous year Compared to the base year’s usage of 132,488, about 4% decrease Natural Gas (Therms) Usage of 451,243 about 16% decrease from the previous year Compared to the base year’s usage of 442,969, about 2% increase Electricity (kWh) Usage of 23,950,484, about 2% decrease from the previous year Compared to the base year’s usage of 25,754,968, about 7% decrease Water—Domestic (gallons) Usage of 15,152,236, about 8% increase from the previous year Compared to the base year’s usage of 21,475,828, about 29% decrease Water—Irrigation (gallons) Usage of 17,971,448, about 77% increase from the previous year Compared to the base year’s usage of 12,737,682, about 41% increase . Garbage (cost only) Cost of $216,142, about 6% increase from the previous year Compared to the base year’s cost of $151,233, about 43% increase . Comingled and Compost Recycling (cost only) Cost of $70,079, about 12% increase from the previous year Compared to the base year’s cost of $30,713, about 128% increase Normalizing Factors . Buildings and Portable Classrooms size (square feet) 2014/2015 district size is 2,471,519 square feet, a 5% increase from the previous year Compared to the base year size 1,819,332, about 34% increase . Weather (degree days) Puget Sound Energy provides weather normalization data in the form of heating degree days (HDD) and cooling degree days (CDD). These data eliminate the year-to-year variability caused by weather. Renewable Energy Programs The Issaquah School District received grants from Puget Sound Energy to install photovoltaic panels at two of our schools. These programs have education components linked to them. Each system has a computer that displays real time and historical energy generation data in the school. These solar systems are also linked by the internet to other Puget Sound Energy grant solar and wind generation systems. Students can collect data from other generation sites for educational research and reports. Grand Ridge A 2.4 KW wind turbine produced 494 kWh last year generating $74.10 of revenue for Elementary Grand Ridge and is located near the play field on a 35-foot tower. A 5.06 KW Solar Electric Photovoltaic system produced 5,730 kWh last year generating $859.50 of revenue. This system is mounted to the roof above the cafeteria. Liberty High This solar photovoltaic 2.24 KW tracking panels system produced 2,970 kWh generating School $445.50 of revenue for Liberty. This system is mounted on a pole at the NE corner of campus. The panels are mounted on a tracking mechanism that keeps the solar panels facing directly at the sun for maximum energy generation throughout the day. An identical Puget Sound Energy solar panel system is mounted to the roof at Hazen High School few miles away that provides comparison data for a permanently mounted system and Liberty’s tracking system. Students find that Liberty’s tracking system generates about 35% more energy than a fixed system. 1 The district’s annual utility costs for the last four years are as follows: Utility 2014 to 2015 2013 to 2014 2012 to 2013 2011 to 2012 Electricity $2,343,209 $2,367,140 $2,243,054 $2,375,202 Natural Gas $457,061 $485,030 $466,341 $565,897 Water (domestic) $157,485 $145,978 $137,996 $125,688 Water (Irrigation) $178,759 $123,137 $147,483 $118,854 Water (sewer) $174,460 $160,533 $120,038 $110,473 Water (storm water) $28,126 $26,205 $24,723 $23,626 Garbage $216,142 $203,219 $199,095 $171,413 Recycling (comingled) $26,996 $22,341 $68,794 $61,517 Recycling (compost) $40,038 $36,061 $34,782 $34,361 Recycling (yard waste) $3.045 $4,010 $3,794 $2,548 Total $3,625,320 $3,573,654 $3,446,100 $3,589,579 The pie chart shows cost percentages of the four main categories of electricity, natural gas, water, and solid waste. Percentages vary year to year but solid waste is always the smallest and electricity is always the biggest. Details for this year are listed below: . Natural Gas: $457,061 . Electricity: $2,343,209 Includes usage, demand, and reactive charges . Water: $538,830 Includes domestic, irrigation, sewer, and storm water charges . Solid Waste: $286,221 Includes garbage, comingled recycling, compost recycling, and yard waste recycling charges 2 Combined Energy (MBtu) British Thermal Units (Btu) are used to combine electricity and natural gas usage into a single metric. One Btu is defined as: the amount of thermal energy required to raise the temperature of one pound of water by one degree Fahrenheit. To visualize, 1 pint of water weighs about a pound and a 4-inch wooden match, when burned completely, releases about 1 Btu of energy. The district measures energy in millions of Btus, hence the notation “MBtu.” The top graph shows monthly energy usage since 2000, with an added trend line. The trend has been stable for the past 5 years and will remain steady with good building management and investment in efficient technology. The bottom graph shows usage on an 1-year cycle with each line representing a different school year. The most recent is in black and previous years are colored in groups of five, simply to show general trends. We see that usage naturally rises throughout the years as new schools are constructed but this mild winter caused near historic lows, especially in February and March. The warm winter was followed by a hot summer, however, and thus more electricity was required to keep temperatures bearable during July and August. 3 Natural Gas (Therms) This past year had the lowest gas usage since 2009/2010, due mostly to the mild winter. Other helping factors in general are standardized temperature settings and HVAC occupancy scheduling. Buildings are only climate controlled when occupied, and all occupied spaces heat to at least 68°F but cool as low as 55°F when vacant. ISD is the only district in the region with such a robust program and our efforts are reflected in the gas bill. The top graph shows monthly energy usage since 2000, with an added trend line. Weather can cause year-to- year fluctuations but the overall trend is stable despite a growing district. Without a RCM program we would see the trend line increase linearly The bottom graph shows usage on an 1-year cycle with each line representing a different school year. The most recent is in black and previous years are colored in groups of five, simply to show general trends. Only November had higher than normal usage and the rest of the months had about 5-year record lows. February usage in particular was about 47,300 therms, a 10 year historic low. 4 Electricity (kWh) The capital projects department completed a lighting upgrade project for exterior wall lights, parking lot lights, multipurpose and cafeteria rooms, and gymnasiums throughout the district. They installed efficient fixtures and occupancy sensors that will keep usage low for years to come. The top graph shows monthly energy usage since 2000, with an added trend line. Good use of technology helps keep growth in check. For example, all computers are remotely shut down each night around 6 p.m., and most light switches are controlled by occupancy sensors. The bottom graph shows usage on an 1-year cycle with each line representing a different school year. The most recent is in black and previous years are colored in groups of five, simply to show general trends. Dramaticly low usage is apparent in January, February, and March but a mich higher usage occurred in July. This is due to the mechanical cooling load required by this summer’s hot weather. 5 Domestic Water Domestic waster is measured in centum cubic feet (CCF), with 1 CCF equaling about 750 gallons. Rate increases have caused costs to rise even though consumption remains low. The top graph shows yearly usage totals in blue (scale on left side) along with yearly costs in red (scale on right side). Higher water rates are causing costs to increase. Yearly usage is highly variable but has stayed around 20,000 CCF or less. The bottom graph shows usage on an 1-year cycle with each line representing a different school year. The most recent is in black and previous years are colored in groups of five, simply to show general trends. Automatic flushing urinals caused high usage throughout the first 2 years of the program, but were fixed for the 2002/2003 year, and the spike for 2005/2006 was caused by extremely high usage during May and June. In general though, we see a pattern throughout each year as, naturally, less water is used in the months that have winter and spring breaks. 6 Irrigation Water Irrigation costs have also increased although the cost trend is not as apparent as domestic water. Irrigation usage is much more variable year to year, depending on rainfall levels during the summer.