Dana E. Veron

Electric power from offshore wind via synoptic-scale interconnection

World wind power resources are abundant, but their utilization could be limited because wind fluctuates rather than providing steady power. We hypothesize that wind power output could be stabilized if wind generators were located in a meteorologically designed configuration and electrically connected. Based on 5 yr of wind data from 11 meteorological stations, distributed over a 2,500 km extent along the U.S. East Coast, power output for each hour at each site is calculated. Each individual wind power generation site exhibits the expected power ups and downs. But when we simulate a power line connecting them, called here the Atlantic Transmission Grid, the output from the entire set of generators rarely reaches either low or full power, and power changes slowly. Notably, during the 5-yr study period, the amount of power shifted up and down but never stopped. This finding is explained by examining in detail the high and low output periods, using reanalysis data to show the weather phenomena responsible for steady production and for the occasional periods of low power. We conclude with suggested institutions appropriate to create and manage the power system analyzed here.

Meteorology for Coastal/Offshore Wind Energy in the United States: Recommendations and Research Needs for the Next 10 Years

This document is a supplement to “Metorology for Coastal/Offshore Wind Energy in the United States: Recommendations and Research Needs for the Next 10 Years,” by Cristina L. Archer, Brian A. Colle, Luca Delle Monache, Michael J. Dvorak, Julie Lundquist, Bruce H. Bailey, Philippe Beaucage, Matthew J. Churchfield, Anna C. Fitch, Branko Kosovic, Sang Lee, Patrick J. Moriarty, Hugo Simao, Richard J. A. M. Stevens, Dana Veron, and John Zack (Bull. Amer. Meteor. Soc., 95, 515–519) • ©2014 American Meteorological Society • Corresponding author: Cristina L. Archer, University of Delaware, College of Earth, Ocean, and Environment, Newark, Delaware 19716 • E-mail: carcher@udel.edu • DOI:10.1175/BAMS-D-13-00108.2 METEOROLOGY FOR COASTAL/OFFSHORE WIND ENERGY IN THE UNITED STATES Recommendations and Research Needs for the Next 10 Years

Opinion: The time has come for offshore wind power in the United States

Offshore wind turbines have been successfully deployed in Europe since 1991, providing thousands of megawatts of clean energy for multiple nations. Ten years ago, it seemed that the United States would follow suit: The US Energy Policy Act of 2005 directed the Department of the Interior (DOI) to establish an offshore leasing regime in federal waters (generally oceanic waters 3–200 nautical miles from the coast). It appeared to be a crucial step in opening the door to the country’s vast offshore wind resource: turbine installations in the Mid-Atlantic Bight alone could power all United States electricity, automobile transport, and building heat needs (1).

Characterization of Low-Level Winds of Southern and Coastal Delaware

AbstractWinds across the Delaware Peninsula transport pollutants, modify the temperature, and play a critical role within the state’s agricultural and tourism industries. The low-level winds inland and near Delaware’s coastline are characterized using observations from eight meteorological stations operated by the Delaware Environmental Observing System and the National Data Buoy Center from 2005 through 2012. The low-level winds have pronounced dominant directions during the summer (southwest/southeast) and winter (northwest) seasons, with the greatest spatial and temporal variability occurring in the summer. This inhomogeneity was further investigated with a set of simulations of the low-level winds over the Delaware Bay and surrounding landmass using the Weather Research and Forecasting Model for a subset of days from 2006 through 2012. The model was run with three nests, with the inner nest having a 2-km horizontal resolution. The randomly selected days were organized by synoptic type and season. Meso...

Employing Cluster Analysis to Detect Significant Cloud 3D RT Effect Indicators

Three-dimensional cloud field morphology contributes to scene-averaged cloud reflectivity, but climate models do not currently incorporate methods of identifying situations where this contribution is substantial. This work represents an effort to identify atmospheric conditions conducive to the formation of cloud field configurations that significantly affect shortwave radiative fluxes. Once identified, these characteristics may form the basis of a parameterization that accounts for radiative impact of complex cloud fields. A k-means clustering algorithm is applied to observed cloud properties taken from the Atmospheric Radiation Measurement Program tropical western Pacific sites to identify specific cloud regimes. Results from a stand-alone stochastic model, which statistically represents shortwave radiative transfer through broken cloud fields, are compared with those of a plane-parallel model. The aggregate scenes in each regime are examined to measure the bias in shortwave flux calculations due to neglected cloud field morphology. The results from the model comparison and cluster analysis suggest that cloud fraction, vertical wind shear, and spacing between cloudy layers are all important indicators of complex cloud field geometry and that these criteria are most often met in cloud regimes characterized by moderate to strong convection. The cluster criteria are applied to output from the Community Climate System Model (version 3.0) and it is found that the presence of persistent high cirrus cloud in model simulations inhibits identification of specific cloud regimes.

Stochastic Radiative Transfer on Modeled Cloud Fields

Several efforts are currently underway to improve cloud-radiation parameterizations in Global Climate Models (GCMs) by incorporating statistical properties of the cloud field. Although some radiation parameterizations, which are already computationally costly, now incorporate subgrid scale variability in cloud properties, they are not yet capable of using this information in their calculations of the 3-D radiation fields. Before drastic changes are made to such algorithms to incorporate cloud-cloud radiation interactions, the impact of including realistic high-resolution cloud distributions on the shortwave fluxes should be assessed. This letter provides a framework for carrying out such assessments, including a new methodology that blends a stochastic radiative transfer model, high-resolution cloud fields from a mesoscale meteorological model, and a threshold and object identification technique applied to cloud water content fields. This process provides a link between the radiative fluxes calculated in GCMs, where clouds occur at a subgrid scale, and the highly resolved cloud fields in a regional climate model, which can provide cloud field statistics. Two case studies are described herein.

Modeling the electrical grid impact of wind ramp-up forecasting error offshore in the Mid-Atlantic region

The large wind resource and population centers along the Mid-Atlantic Coast of the United States make it an attractive region to develop offshore wind power. Understanding and accurately predicting the meteorology offshore is fundamental to efficient integration of these future wind farms into an electrical grid. Particular interest is focused on anticipating and reducing errors associated with wind ramps, which are characterized by rapid, sustained changes in wind speed over a period of hours. Using meteorological observations from a coastal buoy, we characterize 428 wind ramp-ups between 2005 and 2012 in terms of frequency, duration and magnitude, time and date of occurrence, and large-scale synoptics. From this group, we select 24 case studies that represent typical and extreme ramp-ups at this location and then model the impact that the forecasting error of these ramp-ups could have on the electrical grid. The case studies are modeled with the Weather Research and Forecasting (WRF) model and compared ...

A Characterization of the Delaware Sea Breeze Using Observations and Modeling

AbstractSea-breeze circulations are a prominent source of diurnal wind variability along coastlines throughout the world. For Delaware, the sea breeze is the largest source of variability in the co...