Context and Problem DescriptionThe Government of India has set a target of installing 175 GW of renewable energy capacity by the year 2022, which includes 100 GW from solar, 60 GW from wind, 10 GW from bio-power, and 5 GW from small hydropower. Out of 100 GW solar, 40 GW is targeted from rooftop solar photovoltaics (PV). These renewable targets can lead to a new paradigm for power grid planning and operations.Historically, power distribution utilities were designed to serve low voltage loads within their territories, and for decades their planning works were based on the premise that customers only consume power. During this time, distribution utilities learned customer consumption patterns, identified peak, off-peak, and shoulder hours and crafted proficient planning and operational strategies to match them.Over the past decade, solar PV and wind energy adoption has increased at all scales (transmission and distribution), as illustrated in Figure ES-1. Also, recent and anticipated adoption of battery energy storage systems (BESS) and electric vehicles (EVs) are changing the landscape of supply and demand. Some of these emerging technologies are variable in nature and others are not fully understood, thus posing a need for distribution utilities to update the way that they plan and operate their systems.Opportunities and challenges posed by these technologies (solar PV, BESS and EVs) on the power distribution grid are yet to be comprehended, holistically. Typically, wind farms are planned and built at large scale (100 MW to GW) and interconnected to transmission systems. Solar PV, on the other hand, can either be connected to transmission systems at the GW scale or at rooftops at the kW scale. Thus, challenges and opportunities vary significantly depending on the size and point of interconnection (transmission or distribution system). Figure ES-1. Variable renewable resources integrated on the power grid at transmission and distribution levels are posing challenges for distribution utilities www.nrel.gov/usaid-partnership vii www.nrel.gov/usaid-partnership viiiThis track considers renewable integration at bulk grids and assesses their value addition. In order for distribution utilities such as BYPL to make inform decisions when signing power purchase agreements (PPAs), it is crucial for them to understand how much energy and capacity their contracted renewable energy generators can provide. We address the situation faced by utilities by modeling variable renewable energy (VRE) plants from two perspectives: (1) energy production, and (2) capacity credit. Capacity credit describes the percentage of a plant's nameplate capacity that can be reliably counted on to serve load. The capacity credit perspective is illustrated in Figure ES-2, which shows that effective planning includes the possible contributions of VRE. Use of capacity credit unlocks a unique path for understanding the planning reserves provided by solar PV and wind resources. To demonstrate the value from this research, NREL utilized existing knowledge o...
