The stand alone system is more suitable for remote regions where the cost of connecting to the grid would be so high that installing a totally new generating system with long term benefits would be more advantageous.Emergency backup is provided by a battery bank but on windless days power supply can very low. Not be connected to the grid means being very careful with power useage .
The grid-connected system removes the batteries as storage and supplies electricity straight to the grid on a buy and sell agreement. The idea of being totally self-sufficient is lost and the system as is still relys on grid network. Permission must be gained to connect new devices to the distribution network operator(DNO). The legal and technical requirements makes this system a a lot more comlicated than the latter.
Hydro-Electricity is a perfect method for producing carbon neutral energy, but you must have the required amount of land and a good flow of water across it. Although the outlay for a such a system is substancial, the amount of electricity produced is more than adequate to meet any demands with spare to sell.
The two methods used to harness this power are referred to as over -shot and under-shot.Over-shot is were the flow of water is directed over the top of the waterwheel usually via troughs and under-shot is were the water pushes against the bottom paddles of waterwheel spinning the wheel clockwise.
The advantages over wind power are that a more predictable supply provides electricity at all times and by building a reservoir this increases the regularity of flow.
