Impact of demand response on Electric Vehicle charging and day ahead market operations

The orderly transition of the current electricity grid to a smarter grid facilitates the demand side to increasingly play a proactive role. Enabling technologies within the smart grid framework play a crucial role in alleviating systemic risks associated with capacity shortages, electricity price volatility and congestion by controlling end user electricity consumption through demand response (DR). With the impending large scale adoption of Plug-in Electric Vehicles (PEVs), DR becomes even more important to ensure the utilities are adequately prepared to manage the incremental demand imposed by PEV (Plug in hybrid and pure electric vehicle) charging. This paper evaluates the impact of scheduling the incremental demand imposed by the PEV on day ahead market operations. The objective function is to maximize the ISO (Independent System Operator) net surplus. Standard DC optimal power flow (DCOPF) for the ISO managed day ahead market operations is formulated subject to generation capacity, power balance and transmission line constraints. In the base case simulations, the impact of demand bid elasticity on locational marginal prices (LMPs) and ISO net surplus is evaluated for a 5 bus system. For two PEV penetration (10000 and 50000 PEVs) scenarios and three charging profiles (evening, off-peak and uniform), the impact of PEV charging on LMP, GENCO revenues and LSE payments are evaluated. Preliminary results indicate that percentage increment of the LSE payment vary from 0.6% to 12% over the baseline and LMP increment varies between 0.3 to 10%, depending on the time of charging and the size of the PEV fleet. It was also observed that by incorporating demand bid elasticity, more PEVs can be charged without causing an appreciable increase in the LMPs.