|Acquisition Program: || Objective: ||To develop a containerized solar thermal energy collection and generation system that can produce combined heat and power (CHP) for deployable shelter systems and base camp installations.
|| Description: ||Deployed forces use engine-driven generators and water heaters that burn millions of gallons of logistics fuel. A RSCHP containerized system would allow for off-grid locations to provide at least a portion their own heat and electricity. This would lower fuel consumption, decrease the number of required refueling, and lessen the need for fuel transportation.
For example, it is estimated that a 50 m2 array RSCHP system could generate at least 100 kWh/day. From this, the estimated JP-8 fuel savings would be about 3300 gallons/year per RSCHP system. If there are roughly 800 Forward Operating Bases (FOBs) and each base had 1 RSCHP, the yearly fuel savings would be 2,640,000 gallons (compared to a roughly 30% efficient 30kW 60Hz TQG JP-8 fueled electrical generator). Calculated savings is for electrical production only; it does not include possible water heating savings.
Although 50 m2 is used as an example, the specific objective is to select and integrate the greatest possible amount of solar energy collection and electrical conversion technology that fits within and can be deployed from a standard 20 foot ISO shipping container. To further maximize the overall efficiency of the system water heating can be integrated. The RSCHP system should be modular, scalable, and interact with other power modules to partially satisfy or supplement the energy requirements of the deployment. Electrical power produced would assist in powering deployable shelters or entire camps, including lighting, Environmental Control Units (ECU), and Command & Control equipment. A RSCHP system could be a key contributor to a microgrid system which would store and efficiently manage energy from multiple input sources.
Most solar energy systems that are commercially available are designed for stationary permanent public utility applications. Scaling these systems for portable deployable military applications is the primary challenge. Concept systems can utilize or combine any form of solar energy collection (e.g., trough, Fresnel, heliostat) and any form of solar thermal power generation (e.g., organic Rankine cycle, sterling cycle). It is desired that RSCHP not use conventional generators for deployment or start-up.
Emphasis should be placed on energy conversion efficiency (sun to electricity), energy storage capabilities, and energy produced per unit area of solar collector (kW/m2/day). The main focus of this project is to produce the maximum amount of solar generated electrical power in a package restriction, or cube, of a single 20’x 8’x 8’ standard ISO/CONEX container. The deployable components must be man-portable (the MIL-STD-1472 limit for a 4 person “lift and carry” is 147 pounds) and this requirement and the dimensions of the container will determine the actual area and quantity of the individual collectors. The collectors can be rigid or flexible, troughs or flat, sun tracking or fixed, whichever combination minimizes the cube, weight, and cost, and provides adequate reliability and ruggedness for field applications. The container must include all of the system components. An additional desired specification to be met is the exit hot water temperature. If a solar thermal systems waste heat is used to heat water, the water must be able to reach temperatures of 150o F.
|| ||PHASE I: Research, develop, and design an innovative concept with detailed and quantified arguments for feasibility. Comparisons should be made to present-day technology, as well as other similar applications. A major deliverable required in Phase I will be a detailed prototype system design which outlines the solar collection method, energy conversion/generation techniques, system configuration, deployment method, and energy storage abilities (ex. batteries, molten salt). The prototype design must be supported by credible data showing that the system could provide the proposed output values. Any prediction modeling, calculations, or working examples that can validate the systems feasibility and performance potential should be provided. The hardware deliverable for Phase I will be a small scale (1-2 collectors, plus power generation system) proof-of-concept model validating each technology of the designed system. This includes demonstrating 120V AC electrical production (w/ storage) and potential water heating ability. Deliver a final report specifying how full-scale performance and control requirements will be met in Phase II. The report shall also detail the conceptual design, performance modeling, safety, risk mitigation measures, MANPRINT, and estimated production costs.
|| ||PHASE II: Refine the concept and fabricate a full scale prototype containerized RSCHP that is transportable and deployable, meets electrical power and hot water predictions from phase I, and is sufficiently mature for technical and operational testing, limited field-testing, demonstration, and display. Define manufacturability issues related to full scale production of the prototype system for military and commercial application. Identify safety and human factors and provide user manuals and training to support testing of the equipment.
|| ||PHASE III DUAL USE APPLICATIONS: The initial use for this technology will be to provide electrical power and hot water for military base camp organizational systems. Solar electric and heat is applicable to both military and civilian markets. The Army Strategic Action Plan for Sustainability includes objectives, measures and targets for fuel reduction (30% by 2020). The Army Energy Security Implementation Strategy also has several fuel objectives including: “Objective 2.6 Increase energy efficiency of current and tactical equipment/platforms”. There are also initiatives for Zero-footprint Base Camp, the NetZero Plus Joint Concept Capability Technology Demonstration, and the Force Provider Environmental Technologies Working Group, all of which focus on technology to reduce fuel and water consumption. There are also tax incentives for alternative and renewable energy for home owners and businesses.
|| References: ||
1. "NREL: Concentrating Solar Power Research - Publications." National Renewable Energy Laboratory (NREL). Web. 15 Sept. 2009. http://www.nrel.gov/csp/publications.html.
2. "NREL: Distributed Thermal Energy Technologies - Combined Heat and Power." National Renewable Energy Laboratory (NREL) Home Page. Web. 15 Sept. 2009. http://www.nrel.gov/dtet/heat_power.html.
3. “Advances in solar thermal electricity technology” by D. Mills, Solar Energy, Volume 76, Issues 1-3, January-March 2004, Pages 19-31, Solar World Congress 2001. Available on ScienceDirect.com
4. “Design and thermal analysis of a two stage solar concentrator for combined heat and thermoelectric power generation” by Siddig A. Omer and David G. Infield, Energy Conversion and Management, Volume 41, Issue 7, May 2000, Pages 737-756. Available on ScienceDirect.com
5. “A combined heat and power system for buildings driven by solar energy and gas” by A. C. Oliveira, C. Afonso, J. Matos, S. Riffat, M. Nguyen and P. Doherty, Applied Thermal Engineering, Volume 22, Issue 6, April 2002, Pages 587-593. Available on ScienceDirect.com
6. “Solar energy powered Rankine cycle using supercritical CO2” by H. Yamaguchi, X.R. Zhang, K. Fujima, M. Enomoto and N. Sawada, Applied Thermal Engineering, Volume 26, Issues 17-18, December 2006, Pages 2345-2354. Available on ScienceDirect.com
7. “Micro-combined heat and power in residential and light commercial applications” by M. Dentice d’Accadia, M. Sasso, S. Sibilio and L. Vanoli, Applied Thermal Engineering, Volume 23, Issue 10, July 2003, Pages 1247-1259. Available on ScienceDirect.com
8. United States. U.S. Army. Office of the Deputy Assistant Secretary of the Army for Energy and Partnerships. ARMY ENERGY SECURITY IMPLEMENTATION STRATEGY. U.S. Army, 13 Jan. 2009. Web. http://www.asaie.army.mil/Public/Partnerships/doc/AESIS_13JAN09_Approved%204-03-09.pdf
|Keywords: ||combined heat and power, solar energy, renewable energy, power generation, water heating, off-grid, remote|
Questions and Answers:
Q: Is providing cooling as well as heating and power desirable? We have a technology we could propose that is based upon an innovative heat engine approach that can use the working fluid in a refrigeration loop as well as in a power cycle. This will make the entire system more compact and integrated.
A: Cooling is not specifically requested in this topic.
Q: Is this solicitation limited exclusively to concentrating solar thermal/solar-to-electric conversion, or will competing alternatives (e.g. concentrating solar photovoltaic) also be considered?
A: This solicitation is open to all solar energy harvesting, solar/thermal power generation, thermal/electrical energy storage technologies and any combination thereof that meet topic objectives.
Q: Are colored graphics allowed ?
A: Colored graphics are allowed in proposal submission and are included in the 25-page limit.
Q: Phase I Deliverable: The solicitation document above says "The hardware deliverable for Phase I will be a small scale (1-2 collectors, plus power generation system) proof-of-concept model validating each technology of the designed system. This includes demonstrating 120V AC electrical production (w/ storage) and potential water heating ability".
Does this mean we need to deliver a thermal-to-electric conversion device (such as Stirling Engine) at the end of Phase I? Thank you for your atention to this matter.
A: The goal of the solicitation is to generate a majority of electricity and minority of hot water from a given amount of harvested solar energy.
Since the Phase I period of performance is only six months, the vendor should be either well along in the development process with a power cycle design or must have a good idea on how to apply a COTS power solution to their system concept. While electricity production is not mandatory for phase I hardware demonstration it is desired, especially if the power cycle is novel or developmental. Accordingly, a successful phase I hardware demonstration and/or model should at a minimum show that the selected solar collection device can provide sufficient energy to run the selected power cycle.
Q: Is the system expected or desired to be grid-tie compatible?
If so, what connection is required (230V-50Hz, 120V-60Hz, etc)?
A: 120-VAC single phase 60-Hz output is required for this solicitation and is included in every single generator the Army fields (except the 2-kW set, which is 28-VDC only). Most medium- and large-scale generators (>15-kW) include 120/208V, 3 phase, 4 wire that is re-connectible to 240/416V, 3 phase, 4 wire, both conditions at either 50/60-Hz or 400-Hz depending on the model. The higher voltage outputs and grid-connectibility are desired for an eventual product, but not mandatory for this solicitation.
Q: Is a backup generator desired to sustain loads during periods of low to no solar input and periods during which energy storage has been depleted?
A: From the topic description "It is desired that RSCHP not use conventional generators for deployment or start-up." Therefore, potential offerors should assume that a backup generator will be available on site and should not be included in the container.
Q: How much energy storage is required?
If no limit, should emphasis be placed on cost or how much energy storage you can provide within the constraints of the requirements?
A: No specific requirement for size of energy storage subsystem, however, there must be one included in the overall system design. The emphasis should be placed on how much energy storage can be provided within constraints of topic requirements.
Q: Are their any weight limits for the system aside from the deployable components and the containers max payload? A standard 20' ISO container has a max payload of ~62,000lbs.
A: There are no other weight limits/restrictions for the RSCHP system besides those listed in the topic.
Q: Where are we to assume the deployment location? Or does the system need to be designed for all climates (artic, desert, high elevations, etc.)?
A: Potential offerors should assume the RSCHP system could be deployed anywhere in the world, thus should be designed for operation in all climates.