Energy Management Strategies at Metropolitan Water District Roy L Wolfe, Ph.D. Japan U.S. Joint Conference on Drinking Water Quality Management and Wastewater Control California Water and Energy March 2, 2009 California is the third-largest state in the U.S. by land area. Its geography is diverse and includes foggy coastal lands, alpine mountain ranges, hot and arid deserts, and a fertile central valley. The Central Valley, one of the most productive farming areas in the world, dominates the central portion of the state. California is the most populous state in the U.S. In 2006, its population exceeded 37 million people and was one of the fastestgrowing states. This large population drives the interlinked demands for water and energy in the state. The water-energy nexus in California is highlighted by the fact that two-thirds of the state s precipitation occurs in Northern California while two-thirds of the population resides in Southern California. Separating Southern California from the rest of the state is a series of east-west trending traverse mountain ranges, including the Tehachapi. California has made significant investments in conveyance projects to address this north-south water imbalance. Eight large water projects have been constructed since the mid-1930 s to lift and transport water over mountain ranges and across hundreds of miles of land for use in other parts of the state to supply agricultural needs in the Central Valley and the growing metropolitan areas of Los Angeles and San Diego. The movement of water on this scale requires considerable energy resources. The California Energy Commission (CEC) estimates that water-related energy use consumes 19% of the state s electricity and 30% of its natural gas usage every year, and demand is growing. Although lifting water over mountain ranges requires a significant amount of pumping energy, CEC s analysis indicates that over 73% of water-related electricity consumption occurs with the end user in the residential, commercial and agricultural sectors. Electricity consumed in California is generated by a mix of energy resources. More than 60% of California s electricity is generated by greenhouse gas-producing natural gas and coal, and less than 12% is generated from renewable resources. Electricity generation contributes 23% of California s greenhouse gas emissions. In 2006, California enacted Assembly Bill 32 to reduce greenhouse gas emissions in the state. AB 32 requires a statewide reduction of greenhouse gas emissions to 1990 levels by 2020. Energy Management at Water Agencies Energy management is a critical concern to water agencies due to rising cost, increasing energy demands of advanced water treatment technologies and the need to address greenhouse gas emissions. From 1996 to 2005, California experienced an average retail electrical rate increase of 3%. This rate is expected to range from 5 to 20% by 2013 as a result of increased integration of renewable energy supplies. Water agencies face increased energy consumption by new water treatment technologies. Advanced treatment techniques are implemented to meet increasingly stringent water quality requirements. Ultraviolet disinfection, advanced filtration and ozonation are added to or replace conventional treatment technology. Increased 1-1-
electricity needs require greater levels of reliable electricity delivery systems. These issues drive water agencies to manage energy use to reduce costs and maintain reliable water quality compliance. Metropolitan Water District Metropolitan Water District (MWD) is a public agency charged with providing its service area with adequate and sufficient supplies of high quality water. MWD was incorporated in 1928 by an Act of the California Legislature to serve its 13 original founding Member Agencies. Today, MWD provides water to 26 cities and water agencies serving more than 18 million people in six counties. On average Metropolitan delivers 1.9 billion gallons of water per day. MWD imports water to its service area through two significant conveyance projects. The Colorado River Aqueduct (CRA), a 242-mile system of canals, tunnels, and buried conduits driven by five pumping plants, is owned and operated by MWD and is capable of delivering 1.3 million acre feet of water a year from Lake Havasu on the Colorado River. MWD also imports water from Northern California as a contractor on California s State Water Project (SWP) a massive system of 17 pumping plants, 29 dams and reservoirs, 8 hydroelectric plants and 675 miles of aqueducts, tunnels and pipelines. During normal water supply years, the CRA supplies about 36% of Southern California s needs and the SWP supplies about 19%. The balance of Southern California s water needs are met by local water supplies. MWD s water treatment and distribution system consists of five water treatment plants with a combined treated water capacity of 2,580 million gallons per day, 775 miles of distribution pipelines, more than 400 water connections to member agencies, 16 hydroelectric power plants, and numerous water storage reservoirs and support facilities. Energy Management Program MWD initiated its Energy Management Program to ensure its facilities are designed, constructed and operated in an energy-efficient, cost-effective and sustainable manner. Four strategies were developed to achieve this goal: reduce greenhouse gas emissions, improve energy efficiency and energy conservation, manage power resources in a cost-effective manner, and implement cost-effective renewable energy projects. MWD has inventoried its greenhouse gas emissions and reported this information to the California Climate Action Registry. Approximately 95% of MWD s emissions are indirect and result from electricity purchased to operate its facilities. The remainder of emissions comes from mobile sources and stationary combustion equipment. MWD is reducing direct emissions by increasing the percentage of fuel-efficient hybrid vehicles in its fleet and increasing the efficiency of gas-fired equipment. MWD is also reducing indirect emissions by improving efficiency, promoting energy conservation and installing renewable energy systems. Renewable Energy Technologies MWD is pursuing cost-effective renewable energy projects to reduce purchased electricity required to operate its facilities. MWD has a long history of hydroelectric energy generation and currently operates 16 hydro plants along its distribution system. With a combined installed capacity of 140 MW, MWD generated 523,000 MWh of non-polluting, greenhouse gas emission-free energy and netted revenues of $26 million in 2006. Engineering staff is currently assessing the feasibility to expand total generation capacity. 2-2-
Solar PV projects are also in progress at MWD facilities. The first, a 1-MW capacity project, is in construction at a water treatment plant. When completed in April 2009, this plant will satisfy approximately ½ of the current demand and supply almost 25% of annual electricity consumption. Studies are underway for an additional 10- MW of solar PV capacity to be brought on-line during the next four years. These projects will be located at MWD facilities and may utilize alternate acquisition methods such as power purchase agreements. While MWD fully supports the development of renewable energy projects to meet its needs and the greater needs of California, significant obstacles exist. One considerable obstacle is cost. Renewable energy remains more expensive than fossil fuel alternatives. This pricing condition will realign as renewable energy technologies become more cost-effective and carbon-based energy alternatives are priced according to their climate change and environmental impacts. Cost also plays a big part in the required upgrade and construction of transmission systems to carry renewable energy from remote locations to densely populated urban areas. In addition, certain renewable energy technologies such as solar PV and wind are inherently intermittent and variable. These systems require additional flexible energy resources in order to maintain reliable electricity grid operation. MWD, like other water agencies, is faced with greater electricity demands for higher cost energy supplies. We intend to continue our energy management strategies and broaden them where possible to continue energy efficiency and conservation activities and implement cost-effective renewable energy projects. MWD is also developing a greenhouse gas reduction policy proposal for consideration and adoption by its Board of Directors. The policy, if adopted, would define emission reduction targets on a short-term and long-term basis. 3-3-
Energy Management Strategies at Metropolitan Water District Roy L Wolfe, Ph.D. Japan U.S. Joint Conference on Drinking Water Quality Management and Wastewater Control March 2, 2009 Topics California Water & Energy Energy Management at Water Agencies Metropolitan Water District Energy Management Program Next Steps -4-
California 2006 Gross domestic product $1.6 trillion (11.5% of U.S. GDP) Population exceeded 37.4 million State added 462,000 residents (1.2% growth rate) Expected population in 2040: more than 54 million Largest growth in Central Valley Population growth stresses energy system California Water Today Los Angeles Aqueduct State Water Project Colorado River Aqueduct Local -5-
California Water & Energy Energy demand grows with water demand Water use consumes significant amounts of electricity Northern California has 2/3 of state s precipitation; Southern California has 2/3 of the population Eight large water projects take and transport water for use in other areas Water-Related Energy Use In California % of Total GWH (2006) -6-
California Gross System Power 2007 Nuclear 14.8% Natural Gas 45.2% Renewable 11.8% Large Hydroelectric 11.7% Coal 16.6% California Total = 302,072 GWh Greenhouse Gas Emissions More than 60% of electricity used in state is produced from fossil fuel combustion Electricity generation contributes 23% of state GHG emissions More than 50% of electricity-related GHG emissions come from imported power -7-
California s Initiative to Reduce Greenhouse Gas Emissions AB 32 Reduce state-wide greenhouse gas emissions to 1990 levels by 2020 Energy Management Importance to Water Agencies Cost Energy intensive water treatment technologies Greenhouse gas emissions related to energy generation -8-
Electric Price Volatility Energy Price (cents/kwh) California Historical Retail Electricity Rates Source: Energy Information Administration Energy Intensive Water Treatment Technologies Conventional Treatment (CT) Ultraviolet Disinfection Ozone Microfiltration / Ultrafiltration Nanofiltration / Reverse Osmosis -9-
Energy Intensive Water Treatment Technologies Est. Increase in Annual Energy Cost (100 MGD) Source: AWWA Research Foundation Effect of Implementing Energy Intensive Water Treatment Technologies Dramatically increased annual energy costs Increased dependence on reliable energy sources Drives water agencies to energy management options to reduce costs and maintain water quality compliance -10-
Metropolitan Water District Service Area Metropolitan Water District of Southern California 6 counties; 5,200 Sq. Miles 18+ million people Regional economy: $600+ Billion Projected growth: ~220,000 people / year Metropolitan provides about half of Southern California s supply LAKE SHASTA LAKE OROVILLE Where Southern California Gets its Water Bay-Delta LOS ANGELES AQUEDUCTS STATE WATER PROJECT METROPOLITAN WATER DISTRICT SERVICE AREA LOCAL COLORADO RIVER AQUEDUCT -11-
Southern California s Water Supplies State Water Project Imports 36% Colorado River Aqueduct Imports 19% Local 45% SWP West Branch Jensen (1972) MWD System SWP East Branch Weymouth (1941) Diemer (1963) Mills (1978) Colorado River Aqueduct Major MWD Facilities: 242 mile aqueduct 775 miles of pipelines 7 major pumping stations 5 water treatment plants 16 hydroelectric plants Skinner (1976) -12-
Metropolitan s Net Power Costs (2007) CRA $21.3 M 1.4 M MWh 713 TAF Other $8.6M 0.08 M MWh SWP $213.5 M 4.4 M MWh 1.52 MAF Total Power Cost = $243.4 M Total Net Energy Used = 5.9 M MWh Energy Management Program Drivers Climate change Greenhouse gas emissions Risk mitigation Cost control -13-
Metropolitan s Energy Mgmt Program Goal: Design, Construct and Operate facilities in an Energy Efficient, Cost-Effective and Sustainable Manner Strategies: Reduce GHG emissions Improve energy efficiency and energy conservation Manage power resources in the most costeffective manner Implement renewable energy projects MWD Carbon Footprint Colorado River Aqueduct & Water Treatment Facilities -14-
Reduce Greenhouse Gas Emissions Increase number of hybrid vehicles in sedan fleet Improve boiler operations & efficiency at administration buildings Improve Energy Efficiency & Promote Conservation Retrofit lighting systems Install Variable Frequency Drives Promote energy and sustainability awareness -15-
Manage Power Resources MWD Small Hydro Power Plants Energy sold through power contracts Maximize power generation CRA Energy Resources Hoover Dam (supplies ~ 50% CRA power) Parker Dam (supplies ~ 20% CRA power) Consumption & Renewable Generation -16-
Consumption & Renewable Generation Renewable Energy Technologies -17-
Hydroelectric Generation Original HEP program completed in late 1970 s early 1980 s 16 HEPs located throughout distribution system 122-MW dependable capacity 523,000 MWh generated (2006) Generated $26M revenue (2006) All energy contracted or sold on wholesale market HEP Expansion Assessment completed Metropolitan Small Hydro Power Plants CASTAIC DAM & LAKE 140 MW Installed Capacity 523,000 MWh (2006) $26 M Revenue (2006) LOS ANGELS COUNTY SAN BERNARDINO COUNTY LEGEND POWER PLANT MORRIS RESERVOIR SILVERWOOD LAKE VENTURA COUNTY LOS ANGELS COUNTY Upper Middle Feeder Feeder GARVEY RESERVOIR LIVE OAK RESERVOIR Rialto Upper Pipeline SAN BERNARDINO COUNTY RIVERSIDE COUNTY PACIFIC OCEAN Lower Feeder Colorado LAKE PERRIS River Aqueduct SANTIAGO RESERVOIR LAKE MATHEWS DIAMOND VALLEY LAKE SAN JOAQUIN RESERVOIR EL TORO RESERVOIR ORANGE COUNTY RIVERSIDE COUNTY LAKE SKINNER RIVERSIDE COUNTY SAN DIEGO COUNTY -18-
First 1-MW project in construction On-line April 2009 Capital Cost: $8 10 Million Solar Power Expect $5 Million rebate through California Solar Initiative Will generate 2,400 MWh / year (approx. 22% of annual use) Studies underway for an additional 10-MW at various facilities Assessing Capital acquisition vs. Power Purchase Agreements Colorado River Aqueduct Wind Power Meteorological data collected Analysis indicates average wind speed too low for economical plant Further studies planned Monitor wind turbine design progress & efficiency improvements -19-
Issues Impacting Development of Renewable Energy Cost Transmission capacity & reliability Intermittent/variable nature of solar PV and wind energy Technological advances Renewable / Low Emission Power Costs Power Costs -20-
Next Steps for Metropolitan Continue energy efficiency & conservation activities Continue implementation of cost effective Renewable Energy projects: Solar PV Hydroelectric Power Plant Expansions Wind Energy Develop Board policy to address reduction of greenhouse gas emissions -21-
Roy L Wolfe, Ph.D. Metropolitan Water District rwolfe@mwdh2o.com -22-