A scraper attachment for mounting onto sponges used in cleaning applications is described. The solar panel includes a plurality of photovoltaic sub-modules, wherein at least two of photovoltaic sub-modules in the plurality of photovoltaic sub-modules are electrically connected in parallel. A first circuit board is connected to the plug interface contacts and a second circuit board is connected to the plug interface contacts and the output terminals. The concentrate waste stream and domestic wastewater stream may be combined at a ratio of between 20% volumetric flow rate and 75% volumetric flow rate to produce a blended stream.