Increasing penetration of small-scale intermittent distributed energy resources (DER) such as solar/wind in the power system poses frequency regulation problems due to the reduced system inertia. This paper proposes a new entity, namely, renewable energy aggregators (REA), which enables several small-scale renewable energy generators (SREG) and energy storage systems (ESS) to enhance the frequency stability in low-inertia systems. REA participates in the electricity market and provides frequency regulation services by employing dynamic schedule and control strategies (DSCS). The proposed DSCS consists of forecasting and frequency regulation blocks to schedule appropriate amount of renewable energy in real-time. It utilizes individual weather conditions such as solar insolation and wind speeds for SREG and determines variable de-loaded coefficients to energy spilling or wastage. The efficacy of DSCS based REA under both open-loop and closed-loop simulation studies indicate improved frequency regulation performance under varying weather conditions and load fluctuations.