Sean James

The article explores the possibility of reducing carbon emissions in the construction industry by using sustainable carbon-storing materials in concrete masonry unit (CMU) buildings. It mentions that the researchers conducted a pilot demonstration using alkali-activated cement containing algae-derived carbon-storing limestone and algae-based CMUs, which showed promising results in achieving carbon-negative construction and reducing embodied carbon in building materials.

Modern data centers consume large amounts of electricity, resulting in high operational costs. The efficiency of a data center power distribution system can be increased and the operational cost reduced if the number of power conversion stages can be minimized and more efficient converters, such as wide bandgap converters, are used. This can be achieved by using dc distribution voltage at the rack level by eliminating extra conversion stages. In this paper, benchmarks for both ac and 380-V dc… Show more

Modern data centers consume large amounts of electricity, resulting in high operational costs. The efficiency of a data center power distribution system can be increased and the operational cost reduced if the number of power conversion stages can be minimized and more efficient converters, such as wide bandgap converters, are used. This can be achieved by using dc distribution voltage at the rack level by eliminating extra conversion stages. In this paper, benchmarks for both ac and 380-V dc data centers were developed and efficiency analyses were performed for an entire year. The impact of integrating photovoltaic (PV) systems into the data centers has also been analyzed in both cases in terms of efficiency. The results show that 380-V dc data centers are more efficient than ac data centers with and without PV integration. Furthermore, the reliability of an ac system was compared with a 380-V dc architecture with Tier-IV standard. Monte-Carlo simulations were used to perform reliability analyses for different levels of redundancy in the uninterruptible power supply system for both cases. The simulation results showed that the 380-V dc distribution system had a higher level of reliability than the ac distribution system in data centers. Show less

Off-grid power generation has been demonstrated in datacenters through the deployment of site-specific centralized power plants utilizing gas turbine or fuel cell-based power generation. Because power is centrally generated, power distribution requires a high voltage power grid within the datacenter with its ancillary storage and conditioning requirements and equipment. An alternative approach is a completely decentralized distributed power generation system in which fuel cells deployed within… Show more

Off-grid power generation has been demonstrated in datacenters through the deployment of site-specific centralized power plants utilizing gas turbine or fuel cell-based power generation. Because power is centrally generated, power distribution requires a high voltage power grid within the datacenter with its ancillary storage and conditioning requirements and equipment. An alternative approach is a completely decentralized distributed power generation system in which fuel cells deployed within individual server racks providepower localized to that rack only. Among other advantages,such an approach also greatly increases the ability to modulate and control power to individual rack units. Because the SolidOxide Fuel Cells (SOFC) proposed in this approach are air-cooled and have extremely high air exhaust temperatures, of order 800 oC, the optimal energy efficient design of an over alllocalized fuel-cell power generation system should also consider the opportunities to recover and re-use the waste heat.

(PDF) Waste Heat Recovery From Distributed Rack-based Fuel Cells Using Thermoelectric Generators. Available from: https://www.researchgate.net/publication/326708444_Waste_Heat_Recovery_From_Distributed_Rack-based_Fuel_Cells_Using_Thermoelectric_Generators#fullTextFileContent [accessed Jul 16 2024]. Show less

In this study, the National Fuel Cell Research Center is working with Microsoft to investigate a new data center concept that includes the detailed integration of fuel cell technology into server racks. The concept could eliminate the need for backup power and potentially introduce significant emissions reductions and energy savings while enhancing data center availability. The concept was experimentally verified using a hydrogen-fueled 10 kW proton exchange membrane fuel cell stack and system… Show more

In this study, the National Fuel Cell Research Center is working with Microsoft to investigate a new data center concept that includes the detailed integration of fuel cell technology into server racks. The concept could eliminate the need for backup power and potentially introduce significant emissions reductions and energy savings while enhancing data center availability. The concept was experimentally verified using a hydrogen-fueled 10 kW proton exchange membrane fuel cell stack and system as the distributed direct current power source, eliminating the need for power conversion or distribution in the data center and the utility grid outside of the data center. The subsequent evaluation of a natural gas fueled 2.5 kW solid oxide fuel cells stack and system was tested and demonstrated to meet the dynamic DC power demands of servers. Both the steady state performance and the dynamic load following capability of the SOFC stack and system are evaluated and characterized. Show less

Fuel cells are a promising power source for future datacenters, offering high energy efficiency, low greenhouse gas emissions, and high reliability. However, due to mechanical limitations related to fuel delivery, fuel cells are slow to adjust to sudden increases in data center power demands, which can result in temporary power shortfalls. To mitigate the impact of power shortfalls, prior work has proposed to either perform power capping by throttling the servers, or to leverage energy storage… Show more

Fuel cells are a promising power source for future datacenters, offering high energy efficiency, low greenhouse gas emissions, and high reliability. However, due to mechanical limitations related to fuel delivery, fuel cells are slow to adjust to sudden increases in data center power demands, which can result in temporary power shortfalls. To mitigate the impact of power shortfalls, prior work has proposed to either perform power capping by throttling the servers, or to leverage energy storage devices (ESDs) that can temporarily provide enough power to make up for the shortfall while the fuel cells ramp up power generation. Both approaches have disadvantages: power capping conservatively limits server performance and can lead to service level agreement (SLA) violations, while ESD-only solutions must significantly overprovision the energy storage device capacity to tolerate the shortfalls caused by the worst case (i.e., largest) power surges, which greatly increases the total cost of ownership (TCO). Show less

To improve the reliability and the energy efficiency of data centers, as well as to reduce infrastructure costs and environmental impacts, we experimentally evaluated in-rack powering of servers with a hybrid 12 kW Proton Exchange Membrane Fuel Cell (PEMFC) and battery system. The steady state and the transient performance of the PEMFC and battery in response to dynamic AC loads and real server loads have been evaluated and characterized. The PEMFC system responds quickly and reproducibly to… Show more

To improve the reliability and the energy efficiency of data centers, as well as to reduce infrastructure costs and environmental impacts, we experimentally evaluated in-rack powering of servers with a hybrid 12 kW Proton Exchange Membrane Fuel Cell (PEMFC) and battery system. The steady state and the transient performance of the PEMFC and battery in response to dynamic AC loads and real server loads have been evaluated and characterized. The PEMFC system responds quickly and reproducibly to load changes directly from the server rack. Peak efficiency of 55.2% in a single server rack can be achieved. The effect of fuel cell coolant temperature on the hybrid system transient behavior is also captured and evaluated. The observed PEMFC transient responses obtained from the experiments were used to design the size of the energy storage component for the hybrid system. Simulations and analysis of various types of energy storage devices for the hybrid system were carried out. To provide power to meet the most significant transient demand, energy storage capacity greater than 0.3 kWh is required for all battery types, while only 0.053 kWh capacity is required for the ultracapacitor. During charging, the ultracapacitor uses the shortest amount of time to recover to the original SOC, while the charging duration for the lead acid battery is twice as long as that of the ultracapacitor. Show less

We consider the use of fuel cells for powering data centers, based on benefits in reliability, capital and operational costs, and reduced environmental emissions. Using fuel cells effectively in data centers introduces several challenges and we highlight key research questions for designing a fuel cell based data center power distribution system. We analyze a specific configuration in the design space to quantify the cost benefits for a large scale data center, for the most mature and commonly… Show more

We consider the use of fuel cells for powering data centers, based on benefits in reliability, capital and operational costs, and reduced environmental emissions. Using fuel cells effectively in data centers introduces several challenges and we highlight key research questions for designing a fuel cell based data center power distribution system. We analyze a specific configuration in the design space to quantify the cost benefits for a large scale data center, for the most mature and commonly deployed fuel cell technology, achieving over 20% reduction in costs using conservative projections. Show less

In this paper, we argue that servers can be sent to homes and office buildings and used as a primary heat source. We call this approach the Data Furnace or DF. Data Furances have three advantages over traditional data centers: 1) a smaller carbon footprint 2) reduced total cost of ownership per server 3) closer proximity to the users. From the home owner’s perspective, a DF is equivalent to a typical heating system: a metal cabinet is shipped to the home and added to the ductwork or hot water… Show more

In this paper, we argue that servers can be sent to homes and office buildings and used as a primary heat source. We call this approach the Data Furnace or DF. Data Furances have three advantages over traditional data centers: 1) a smaller carbon footprint 2) reduced total cost of ownership per server 3) closer proximity to the users. From the home owner’s perspective, a DF is equivalent to a typical heating system: a metal cabinet is shipped to the home and added to the ductwork or hot water pipes. From a technical perspective, DFs create new opportunities for both lower cost and improved quality of service, if cloud computing applications can exploit the differences in the cost structure and resource profile between Data Furances and conventional data centers. Show less

The IT industry is the fastest growing sector in US en-ergy consumption. Improving data center energy efficiency is a pressing issue with significant economic and environ-mental consequences. Heat distribution is a key operational parameter that affects data center cooling and energy con-sumption. However, typical data centers lack effective fine-grained sensing systems to monitor heat distribution at a large scale. In this paper, we motivate the use of sensor net-works as a dense… Show more

The IT industry is the fastest growing sector in US en-ergy consumption. Improving data center energy efficiency is a pressing issue with significant economic and environ-mental consequences. Heat distribution is a key operational parameter that affects data center cooling and energy con-sumption. However, typical data centers lack effective fine-grained sensing systems to monitor heat distribution at a large scale. In this paper, we motivate the use of sensor net-works as a dense instrumentation technology to understand and control cooling in data centers. We present Microsoft Research Genomote sensors designed for data center mon-itoring, and the RACNet for reliable data acquisition. We describe lessons learned from early pilot deployments, and discuss architectural and technical challenges in developing data center sensor networks. Show less