Professional football is, in terms of the risk of injury, a high-risk occupation. The objects of this study are to examine the ways in which professional footballers respond to and cope with injury and, in this context, we focus on the culture of `playing hurt' in football. The study involved semi-structured interviews with former and current professional footballers as well as interviews with club doctors and physiotherapists. The interviews focused centrally on the players' experiences of injury and rehabilitation, the attitudes of players, coaches/managers and others towards injury, and their relationships, particularly in the context of injury, with the club doctor and physiotherapist(s). Our findings indicate that incurring an injury has a number of well-understood meanings for players. The meanings associated with pain and injury, as well as the status of players who are unable to play because of injury, can only be fully understood by locating these shared meanings within the network of social relations characteristic of professional football. It is argued that the almost unrelenting pressure on players to continue playing through injury exacts a heavy cost from many players in terms of pain, injury and long-term chronic disability.

SummaryThe widespread adoption of demand response (DR) enabled appliances and thermostats can result in a significant reduction to peak electrical demand and provide potential grid stabilization benefits. GE Appliances has developed a line of appliances that will have the capability of offering several levels of demand reduction actions based on information received from the utility grid, often in the form of price or grid status. However due to a number of factors, including the number of DR-enabled appliances available at any given time, the reduction of diversity factor due to the synchronizing control signal, and the percentage of consumers who may override the utility signal, it can be difficult to predict the aggregate response of a large number of residences. The effects of these behaviors can be modeled and simulated in the Pacific Northwest National Laboratory (PNNL) developed open-source software, GridLAB-D™, including evaluation of the appliance controls, improvement to current algorithms, and development of aggregate control methodologies.This report is the first in a series of three reports describing the potential of GE Appliances' DR-enabled appliances to provide benefits to the utility grid. The first report will describe the modeling methodology used to represent the appliances in the GridLAB-D simulation environment and the estimated potential for peak demand reduction at various deployment levels. The second and third reports will explore the potential of aggregated group actions to positively impact grid stability, including frequency and voltage regulation and spinning reserves, and the impacts on distribution feeder voltage regulation, including mitigation of fluctuations caused by high penetration of photovoltaic distributed generation and the effects on volt-var control schemes.In Section 2, the effects and potential benefits of appliances on the power system were studied by modeling GE Appliances' DR-enabled appliances in GridLAB-D. GridLAB-D is an open-source, state-of-the-art software designed at PNNL for the Department of Energy's Office of Electricity Delivery and Energy Reliability to simulate the complexities of the smart grid from the substation down to the end-use load. Multi-state appliance models were used to represent not only the baseline instantaneous power demand and energy consumption, but the control systems developed by GE Appliances. This enabled the modeled appliances to respond to load reduction signals, as well as the change in behavior of the appliance in response to the signal. This included the power and energy consumption and the time horizon over which they operate for the various operational modes, and how changes in the DR control signal affect load behavior. This gives insight into the potential for short term versus longer term reduction in power consumption, and allows for exploration of different DR control signals without developing a new model for each case. Additionally, it gives insight into how to improve the effectiveness of the DR-enabled appliances...

SummaryIncreasing penetration of heat pump water heaters (HPWHs) in the residential sector will offer an important opportunity for energy savings, with a theoretical energy savings of up to 63% per water heater 1 and up to 11% of residential energy use (EIA 2009). However, significant barriers must be overcome before this technology will reach widespread adoption in the Pacific Northwest region and nationwide. One barrier is that the demand response (DR) performance and characteristics of HPWHs is unknown. Previous research has demonstrated the potential of electric resistance water heaters (ERWHs) to provide significant grid stability and control benefits through demand-side management, or DR, strategies (Diao et al. 2012). However, if ERWHs are to be replaced with HPWHs to improve residential energy efficiency, it is important to understand the DR characteristics of HPWHs and how these characteristics will impact DR programs and overall grid stability now and in the future.This project evaluates and documents the DR performance of an HPWH as compared to an ERWH for two primary types of DR events: peak curtailments and balancing reserves. The experiments were conducted with General Electric (GE) second-generation "Brillion™"-enabled GeoSpring™ hybrid water heaters in the Pacific Northwest National Laboratory (PNNL) Lab Homes 2 , with one GE GeoSpring water heater operating in "Standard" electric resistance mode to represent the baseline and one GE GeoSpring water heater operating in "Heat Pump" mode to provide the comparison to heat pump-only DR. Signals were sent simultaneously to the two water heaters in the side-by-side PNNL Lab Homes under highly controlled, simulated occupancy conditions. It is expected that "Hybrid" DR performance, which would engage both the heat pump and electric elements, could be interpolated from these two experimental extremes.Based on the data collected in these DR experiments, both ERWHs and HPWHs are capable of performing peak curtailment and regulation services. However, their characteristics differ, as can be seen in Table 5.1, which shows the average impact on power use during the DR event, energy use during the DR event, and daily energy use for ERWH and HPWH for peak curtailment, 1-2 hour balancing events when generation and load are mismatched either due to higher load than generated power (INC events) or greater power generation than available load (DEC events). In general, the HPWH has much lower power use than the ERWH (587 Watts [W] versus 4,650 W) and provides approximately 38% of the potential to reduce load for peak curtailment or INC balancing events of the ERWH. The ERWH provides more dynamic response with a high magnitude of power increase or decrease per water heater. However, the HPWH has longer and more frequent operating times, which means the HPWH has a higher likelihood of being able to respond when an INC event or peak curtailment is called for. In addition, the inherent efficiency savings of HPWHs (61.7 ± 1.7%, as measured in the PNNL Lab Homes) will resul...

Printed in the United SummaryThe widespread adoption of demand response (DR) enabled appliances and thermostats can result in significant reduction to peak electrical demand and provide potential grid stabilization benefits. GE has developed a line of appliances that will have the capability of offering several levels of demand reduction actions based on information received from the utility grid, often in the form of price or grid status. However due to a number of factors, including the number of DR-enabled appliances available at any given time, the reduction of diversity factor due to the synchronizing control signal, and the percentage of consumers who may override the utility signal, it can be difficult to predict the aggregate response of a large number of residences.This report is the second in a series of three reports describing the potential of GE's DRenabled appliances to provide benefits to the utility grid. The first report described the modeling methodology used to represent the GE appliances in the GridLAB-D simulation environment and the estimated potential for peak demand reduction at various deployment levels. The third report will explore the technical capability of aggregated group actions to positively impact grid stability, including frequency and voltage regulation and spinning reserves, and the impacts on distribution feeder voltage regulation, including mitigation of fluctuations caused by high penetration of photovoltaic distributed generation.In this report, a series of analytical methods were presented to estimate the potential cost benefit of smart appliances while utilizing demand response. Previous work estimated the potential technical benefit (i.e., peak reduction) of smart appliances, while this report focuses on the monetary value of that participation. The effects on wholesale energy cost and possible additional revenue available by participating in frequency regulation and spinning reserve markets were explored. Specifically, historical market data from NYISO and PJM in 2006 were used to estimate the savings available to consumers and/or utilities by engaging demand response capabilities in HVAC systems, water heaters, clothes dryers and washers, dishwashers, refrigerators, freezers, miscellaneous light and plug loads, and cooktop range and ovens. While prices were marginally higher in 2006 than current prices, these were openly available, complete data sets and are used to provide a general indication of the value of smart appliances within a structured market.Historical data from the End-Use Load and Consumer Assessment Program (ELCAP) and current U.S. energy usage by appliance was used to create seasonal, hourly load shapes for an average single family household. The appliance load shapes are available in Appendix B. These were applied against the 2006 NYISO and PJM wholesale energy markets. Estimates were made on the peak shifting capability of each appliance to respond to a TOU/CPP signal designed to significantly shift peak load for six hours on the 15 highest energy c...

To examine the energy, air leakage, and thermal comfort performance of highly insulating windows, a field evaluation was undertaken in a matched pair of all-electric, factory-built "Lab Homes" located on the Pacific Northwest National Laboratory (PNNL) campus in Richland, Washington. The "baseline" Lab Home A was retrofitted with "standard" double-pane clear aluminum-frame slider windows and patio doors, while the "experimental" Lab Home B was retrofitted with Jeld-Wen® triple-pane vinyl-frame slider windows and patio doors with a U-factor of 0.2 and solar heat gain coefficient of 0.19. To assess the window, the building shell air leakage, energy use, and interior temperatures of each home were compared during the 2012 winter heating and summer cooling seasons. The measured energy savings in Lab Home B averaged 5,821 watt-hours per day (Wh/day) during the heating season and 6,518 Wh/day during the cooling season. The overall whole-house energy savings of Lab Home B compared to Lab Home A are 11.6% ± 1.53% for the heating season and 18.4% ± 2.06% for the cooling season for identical occupancy conditions with no window coverings deployed. Extrapolating these energy savings numbers based on typical average heating degree days and cooling degree days per year yields an estimated annual energy savings of 12.2%, or 1,784 kWh/yr. The data show that highly insulating windows are an effective energy-saving measure that should be considered for high-performance new homes and in existing retrofits. However, the cost effectiveness of the measure, as determined by the simple payback period, suggests that highly insulating window costs continue to make windows difficult to justify on a cost basis alone. Additional reductions in costs via improvements in manufacturing and/or market penetration that continue to drive down costs will make highly insulating windows much more viable as a cost-effective energy efficiency measure. This study also illustrates that highly insulating windows have important impacts on peak load, occupant comfort, and condensation potential, which are not captured in the energy savings calculation. More consistent and uniform interior temperature distributions suggest that highly insulated windows, as part of a high performance building envelope, may enable more centralized duct design and downsized HVAC systems. Shorter, more centralized duct systems and smaller HVAC systems could yield additional cost savings, making highly insulating windows more cost effective as part of a package of new construction or retrofit measures which achieve significant reductions in home energy use.