The “pay as you throw” age is here as variable rate programs continue to gain momentum across the country, with some areas reducing disposal tonnage by 40 percent. More than 1,000 communities are expected to adopt a variable rate program in 1994.
Accountability for trash at the collection point is imperative in any variable rate program or pay-by-weight systems. Radio Frequency Identification (RF/ID) technology answers the problems of accountability for such rate programs. Each resident has one or more roll out carts installed with a transponder or “tag” that contains a unique identification number. This number correlates with a profile on the cart customer which is located in the city database. Profiles can contain information such as name, address, size and color of the cart, rate collection and a chronological history of collection and maintenance over a period of time.
A truck equipped with a transponder reader system automatically reads the transponder when the cart is emptied. A date and time is assigned at the instant each cart is read and sent with the ID to the onboard computer, which the stores the daily route data and batch loads it to the city database at the end of the day or the information can be sent via modem the truck to the city database.
Once the route information is in the main database, productivity criteria may be analyzed. Time and motion studies may be conducted to evaluate truck and driver performance, route assignments, time spent at landfills, transfer stations, maintenance garages and other facilities. Having this information allows a manager to discover inefficiency in the operation. Haulers that own carts and distribute them to their waste customers have found that as many as 10 percent of [the carts] can be unaccounted for over long periods of time or never used after initial distribution. Onboard computers can also record damaged or unused carts along a route.
The Texas Instruments Registration and Identification System (TIRIS) has been installed in almost a million carts in 50 communities. The core of the TIRIS technology is the small, passive (battery-free) transponder attached to the cart. The reader system, which is integrated on the trash truck, sends a low-frequency signal that charges the transponder to enable a return signal with each cart’s unique identification code. The entire process is completed in milliseconds. The read-only transponder contains a factory programmed 64-bit or 20-digit identification code.
Two low-frequency RF/ID system options are available on the market today. Most systems are the full duplex type which is characterized by simultaneous powering of the transponder and transmission of data from the transponder back to the reader. However, since the power and read functions must run simultaneously, the read range of the transponder is reduced. TIRIS uses a half duplex signal that uses sequential powering of the transponder followed by transmission of data to the reader.
Due to the associated cost of implementing RF technology, there has been some initial resistance among the waste industry. To install a $5 transponder on a roll cart and then amortize it over the life of the cart becomes an attractive option given the cost reductions due to increased operating efficiency. Taking five percent from operating costs for a few years will more than pay for the technology and bring waste collection to a higher level.
Once waste haulers and municipal leaders experience the benefits of complete automation there will be no turning back. The RF/ID market in the waste management industry in about to explode as the new competitive edge becomes recognized by all players. profitability will no longer come out of mediocrity in waste operations. As costs continue to rise, new technologies will have to be taken advantage of today to ensure economic and environmental survival in the years to come.