Luis Ortiz

On the Spatio-Temporal End-User Energy Demands of a Dense Urban Environment

Krarti Ahmed1, Luis E. Ortiz2, J.E. González2 1Ecole Polytechnique, Paris, France 2Mechanical Engineering Department, The City College of New York, NY 10031 Abstract Many growing major metropolitan centers face increased peak electrical load, especially during extreme heat events. This impacts the reliability of the electric grid raising the costs for energy demands. It is therefore imperative to better understand the energy consumption profile in the building sector for scales of large cities. This understanding is not only paramount to users to avoid peak demand charges but also to utilities to improve load management.

New York City Impacts on a Regional Heat Wave

ABSTRACTHeat waves are projected to increase in magnitude and frequency throughout this century because of increasing global temperatures, making it critically important to acquire improved understanding of their genesis and interactions with large cities. This study presents an application of the method of factor separation to assess combined impacts of a synoptic-scale heat wave, urban land cover, and urban energy and momentum fluxes on temperatures and winds over New York City, New York, via use of high-resolution simulations (1-km grid spacing) with an urbanized version of the Weather Research and Forecasting (WRF) Model. Results showed that factors behaved different throughout the day, with synoptic conditions dominating afternoon temperature contributions (>7°C). At night, combined urban surface factors contributed over 5°C during the heat wave and up to 1.5°C on non-heat-wave days. Positive interactions among all factors during morning and nighttime indicate an amplification of the urban heat islan...