Abstract: A remote resource can be configured to control connectivity of the power generator modules in a string. For example, a respective power generator module can include a current sense circuit that monitors for presence of communication signal. The power generator module can monitor for a presence of a remotely generated control signal over power line that is used by the respective power generator module to convey power to the external load. If the control signal is present on the power line, as generated by the remote resource, the control circuit in the respective power generator module activates the switch to an ON state such that respective activated power generator module is connected in series with the other activated power generator modules. If no keep-alive control signal is detected within a timeout period, the controller deactivates the respective power generator module.

Abstract: Municipal sludge is converted from an environmental problem into soil amendment and electricity. Methane, produced in an anaerobic digester (2), is used partially to generate electricity and partially to dry the concentrated sludge in a rotary dryer (7). Excess heat from the dryer is used to maintain the temperature in the digester at approximately 105.degree. to 130.degree. F. Heavy metals are removed so that the dried sludge can be safely used as a soil amendment.