This paper presents the basic considerations for design of solar photovoltaic-wind-battery-grid connect hybrid power plants(HPPs). For ensuring the successful operation of hybrid power plants at low diesel input and low battery storage requirement, high level of reliability of power supply and reliability of component are essential. This paper provides factors involved in ensuring that high level of reliability of components and power availability is fulfilled in the hybrid plants. For both SPV and wind, the annual energy generation is divided into three regimes: summer, winter and rainy seasons and all these three have to fulfil the load requirement. It is seen that for 30% solar and 70 % wind generation curve is the smoothened with less variation.With improved day ahead predictability of both wind and solar the reliability can be improved considerably.