Power is essential to any manufacturer, and Riverdale Mills, a Massachusetts-based company, has long depended on the Blackstone River for a sizeable amount of what it needs to produce wire mesh fabric products for sectors that include marine, security, construction, and agriculture industries. Below, company CEO Jim Knott explains how tapping into hydropower, and other measures, has enabled the company to control its expenses while reducing its carbon footprint.
WJI: Just how important are non-traditional sources of energy to your company?
Knott: Sustainability is at the core of Riverdale Mills. We have continuously explored options to employ energy-efficient systems and recycling programs. We are also blessed to be located by the Blackstone River, and that source of hydropower has been a huge asset for us in terms of maintaining a low-carbon footprint.
WJI: When did that start?
Knott: When the Knott family purchased and completely renovated the run-down, former textile and paper mill in 1979, they saw the adjacent Blackstone River was a natural source of energy. They restored the circa 1901 Francis Type B water turbine to produce hydropower and rehydrated the adjacent and barren mill pond. Our restoration efforts over the past 40 years have reaped benefits for the ecosystem, the community, employees and visitors, as well as nature lovers. The dam and the hydro-electric turbine increase the dissolved oxygen in the Blackstone River which, in turn, helps to sustain the fish and wildlife population. Our 19-acre pond supports a diverse, healthy and self-sustaining wild-life community. It is home to trout, carp, crappie and catfish as well as snapping turtles, water snakes, beavers, swans, great blue herons and eagles.
WJI: How much work went into hydropower?
Knott: A lot. We now have a computer-automated hydro dam that continuously controls the river flow to assure the required water flows both into the turbine and into the bypass reach. It reduces our use of “traditional” electricity.
WJI: How dependable is the river flow?
Knott: There are times when the flow is low, and then we have to depend on just traditional sources, but over the course of a year we can generate about 162,000 kH. Every bit matters because we have dozens of large systems that run 150 hours a week. Hydropower minimizes our company’s carbon footprint, and both protects and enriches the natural resources, waterways and habitat on its property.
WJI: We hear you invested elsewhere as well.
Knott: We did. We operate a 500kW Combined Heat and Power (CHP) system for our 390,000-sq-ft facility to offset energy costs and minimize reliability on local power providers. The CHP unit can run in an “island mode,” meaning it can be used independently, off the utility grid or in combination with the grid, to support our manufacturing operations. The CHP systems produce electricity and hot water at 80-90% efficiency, compared to the grid’s 30% efficiency, and can cut carbon emissions by about 50%. Since it was installed in 2017, the CHP system has decreased our dependence on local utility providers by approximately 60%. It has reduced our company’s carbon footprint by approximately 3,000,000 kilowatt hours annually. We send the CHP “waste heat” to our coating and galvanizing lines for recovery which further decreases our energy consumption while increasing output. The system supplies an estimated annual energy savings of 2,940 therms. We also replaced our traditional HVAC system with a geothermal heating and cooling system to help keep the building warm in the winter months and cool in the summer. We installed energy-efficient machinery with future technologies to coincide with the lifetime of equipment (rather than stay with the status quo). Finally, we’ve upgraded our existing systems, improved processes and maintenance, and conducted time-intensive staff training.
WJI: It all sounds very expensive.
Knott: Riverdale is committed to our corporate goals of achieving long-term environmental and economic savings. Eco-friendly and energy efficient processes, waste reduction and recycling have been our business priorities since our founding in 1980. Sustainable and environmentally friendly manufacturing is not just right for the planet, it is essential for the safety and sustainability of our facility, our staff, our products and the community in which we operate. The significant investments we made were strategic, laser-focused on the future, and took a concerted effort but the investments are showing dividends. Tapping into solar energy is next on our list but we’ll need to discuss that in another issue!