It’s time to make the sun work for you and create BIG Savings !
Now with a new Solar Panel Power Unit you can use the power of the sun to run your self-contained and stationary compactors.
Solar Powered Compactors
In situations where three phase hydro is not available at the depot site, and where the costs of installing
it are prohibitive, a battery bank with sufficient capacity to cycle the compactor efficiently is necessary.
Solar power can provide an energy source to supply the battery bank and in turn run a compactor. A
solar power system typically includes:
Batteries, which store the energy generated by the panels (e.g., four 6V batteries); and
A supplemental energy source to provide power during periods where there is insufficient
sunlight, such as a generator or connection to hydro.
Best practices related to using solar powered compactors include:
Battery Protection – Storage areas should be designed to prevent batteries from freezing. Low
temperatures can reduce the efficiency of the batteries and extended exposure of batteries to
freezing conditions can cause costly replacements. For example, batteries can be kept within the
attendant building, assuming it is heated. Otherwise, an insulated and heated outside storage
unit for the batteries may be required.
Regular Cleaning – Solar panels require regular cleaning (e.g., removal of snow or wiping off
dust and dirt) to ensure they are operating at maximum efficiency. The frequency of the
cleaning would depend on the season and local conditions at the site. For example, snow will
need to be removed from the panels in the winter, and sites with unpaved or dirt traffic areas
may need to wipe away dust on a daily basis. However, these tasks can be integrated with
regular site house-keeping duties with minimal added cost, whether the site is permanently
staffed or not.
Back-up Energy Source – A solar power system requires a supplemental energy system to
recharge the batteries when solar input and/or temperatures are low (e.g., winter months in
Ontario). Typically, this comes in one of three forms: connection to the hydro grid; a permanent
generator; or a portable generator (which is not recommended). If available, connection to the
hydro grid may be most advantageous because it requires the least amount of maintenance and
operator intervention. Otherwise, a generator would be required, which would require
maintenance and upkeep. Whether it is a portable or permanent generator would depend on
the setup of the solar powered units. For example:
o A portable generator may be useful if there are a few sites using solar power, if an
attendant routinely visits each site, and if the portable generator is of sufficient size to
efficiently charge the batteries. However, this would include an on-going labour cost
and would increase the risk of damage to battery capacity if they are allowed to fall
below a critical charge.
o A permanent generator is likely more advantageous, particularly if only one or two sites
require supplemental power or if the size of the battery installation requires a larger
Arrangement of Solar Panel Array – While some configurations for solar powered compactors
include a small dedicated panel array and batteries for each compaction unit, another option is
to have a larger centralized system of solar panel arrays and batteries to power all the
compactors onsite (see Figure 3). In such a configuration, the compactors would only run one at
a time, either manually cycled by an attendant, or by the timing of automated systems.
Advantages of this type of configuration is that the batteries can be housed in one central
heated storage unit and maintenance/cleaning of the panels becomes easier. Also, the panels
can be situated in the optimum location on the site with respect to collection of solar energy,
rather than attached directly to the compaction containers.
Oversizing the Solar Power Units – When selecting the solar power units, consider upsizing
them (e.g., purchasing a unit 10% larger than the minimum required size). This may help offset
diminished efficiency of the batteries over time and provide some buffer if power requirements
unexpectedly increase. Also, as the light-weighting of recyclable materials continues, volumes of
recyclables will keep increasing and therefore increase how often compaction is required.