Water and energy systems long have been intrinsically intertwined, given electricity's entrenchment as one of a water or wastewater utility's biggest expenditures. But as water suppliers and wastewater service providers grapple with ways to reduce power costs, advance toward "green" energy and participate in the electric industry evolution, there's talk of "new energy."
Consider Orlando, where the Iron Bridge plant treats tens of millions of gallons of sewage, making it far and away the central Florida city's biggest electricity user. As Orlando works to wean itself from power derived from burning coal or natural gas, it's considering working with the regional electric utility to turn some of Iron Bridge's property into a microgrid armed with thousands of solar panels that can churn out cheaper, greener power.
As the nexus of water and "new energy" becomes more common in the water sector's lexicon, Black & Veatch's 2019 Strategic Directions: Water Report survey shows that water and wastewater plant operators are embracing "master plans" meant to optimize their energy use, which unlike labor and chemical costs is something they can influence. Making the most of their data and bringing on more efficient equipment is helping, although water-related utilities also are exploring renewable energy – notably solar – as options in deferring operating costs.
The energy shift is not coming as vigorously as one might expect, perhaps partially because operators are focused on keeping their aging infrastructure functioning rather than thinking about tomorrow's energy scene.
A First Step: Developing an Energy Master Plan
Black & Veatch's annual survey of water industry leaders in North America shows that while two-thirds of respondents see energy management as very or extremely important, just less than half reported having an energy master plan. A little more than one-quarter of respondents said they're not working on such a blueprint in any form – perhaps because they feel they may not need one, given that they may be small utilities serving a small territory, or because their lagoon treatment of wastewater requires scant energy.
Low electricity rates also may be undercutting wider acceptance of new energy in the water industry, considering that nearly three-quarters of respondents to the Black & Veatch survey report paying just a 10 cents or less per kilowatt hour. Regions where those rates are higher – traditionally along the nation's coasts – offer a greater value proposition and incentive to take the upfront financial plunge into renewables.
Even so, according to the survey, renewables clearly are on the table, with three-quarters of respondents considering them. This shows that utilities are essentially scoping out whether there's a business case for solar – or if there is another driver, such as a local population pushing for cleaner, greener energy.
The solar alternative was far and away the popular energy choice among respondents to the poll, not surprisingly, given the shrinking cost of solar equipment and advances in the efficiency and lifespan of the panels. Solar is a logical, credible option because it's a passive, sunshine-collecting system without a lot of operations and maintenance (O&M) demands, which can be handled by outside contractors as needed. Looking at other options for generation, one-third said they were pondering gas generation from biosolids, while one-fifth are weighing hydroelectric options, increasingly on a small-scale basis.
In Solar, Shining Examples of Water Utilities Taking Actions
Some water utilities are taking the dive into new energy, turning shovels in the interest of resilience. And they're finding different ways to pay for it, with everything from federal and local funds to Public-Private Partnerships (P3s).
In northern California's Redding, the local Bella Vista Water District enlisted CalCom Energy – a solar developer and energy services company – to install what's now a 693-kilowatt solar farm that, along with the district's earlier solar array, helps the utility offset three-quarters of its annual electricity usage tied to pumping water. Paid for by a federal grant and district funds, the project is expected to produce $3 million in cost savings over the next quarter century and churn out more than 1 million kilowatt-hours of clean energy per year for the 20,000-customer district with 53 square miles of service territory.
"By leveraging district funds, we managed to maximize our overall investment in locally produced clean energy, which is central to the district's energy strategy to reduce dependence upon retail power purchases and exposure to greatly increasing energy costs," David Coxey, the water district's general manager, said upon announcing the latest project's competition in March 2019.
In Puerto Rico, which struggled to restore power in remote areas after Hurricane Maria ravaged the island's electrical system in 2017, new water and wastewater systems in the form of a half dozen microgrid-powered pumping systems are up and running. They're courtesy of a partnership between South Carolina-based nonprofit Water mission and Blue Planet Energy, an energy storage company out of Hawaii. All six pumping systems run independently of the island's public water utility.
In Las Cruces, New Mexico, local dignitaries convened in March 2019 to celebrate the startup of two new co-generators that convert methane – a byproduct of wastewater processing – and natural gas into efficient energy, saving the city about $220,000 a year.
In Western Australia, that region's chief water supplier – Water Corporation, with 2.6 million square kilometers (or, just over 1 million square miles) of surface territory – announced in early 2019 that it plans to spend $325,000 to install rooftop solar systems on its offices, pump stations, treatment plants and borefields. there are also plans to build an energy generator powered by biogas, a byproduct of wastewater treatment. With expectations that the panels will generate half of the total power to run each site and cut the corporation's yearly emissions by 450 tons, the state's water minister, Dave Kelly calls it leading by example "and doing what they can to reduce greenhouse gases that accelerate climate changes."
And then there's Orlando, which is weighing partnering with the regional electric utility to set up the microgrid station near the city's Iron Bridge sewage plant, the Orlando Sentinel has reported. The system, to be built and owned by the power company, would give one of the state's biggest handlers of sewage coveted resilience in times of emergency. Initial plans for the new energy systems at the 37-year-old plant, which was upgraded in 2005, call for it to produce 1 to 3 megawatts of power.
Getting Off the Sidelines and into the Game
While water and energy often are deemed to be different silos, improving only one of those resources while neglecting the other in what’s an interdependent system is counterproductive when pursuing sustainability and security.
Opportunities to boost energy efficiency, cut greenhouse gas emissions and capitalize on new revenue streams differ among wastewater utilities. Yet beyond being decades-old and traditionally in need of upgrades, a clear commonality exists: the ability to contain or cut energy and operational costs by embracing modern technology.
Utilities can exploit the benefits of the large volumes of available data for greater system efficiency and asset management. And they should know on-site generation of new energy sources — options such as biogas, hydroelectric and renewables — are maturing and gaining sway, with solar generation a natural option for utilities that largely have access to large spaces and rooftops of public buildings.
Funding doesn’t need to be an obstacle. Public-private partnerships or power purchase deals can help pave the way toward sizable, long-term cost savings via traditional solar providers or power purchase agreement (PPA) ventures fashioned to implement energy efficiency work and provide renewable resources with private funding. That financing then receives the “savings” experienced by the water/sewer agency, thereby resulting in no capital spend or increase in operations and maintenance costs.
There is significant conversation, too, about financing and the increased risk. An additional topic of conversation is the impact the shift to renewables will have on water power generation and what role water will play in power generation.
With such climate variability, Australia’s water chief Kelly presses, “what’s important is that we don’t wait but (that we) take every opportunity now to reduce energy use and greenhouse gases,” and “adopting new technology and applying it in the field allows us to learn what works best.”