Questions Regarding Funding Opportunity Announcements

Please contact the email address for questions regarding Funding Opportunity Announcements. Upon the issuance of a FOA, only the Contracting Officer may communicate with Applicants. ARPA-E personnel and our support contractors are prohibited from communicating (in writing or otherwise) with Applicants regarding the FOA. This “quiet period” remains in effect until ARPA-E’s public announcement of its project selections.

ARPA-E will not pre-assess an Applicant’s proposal. Prospective Applicants must review the technical requirements of the FOA and independently determine whether their proposed concept warrants a submission.


ARPA-E Archived Funding Opportunities

DE-FOA-0001607: Request for Information (RFI) on Lower Grade Waste Heat Recovery

ARPA-E seeks input from the waste heat recovery, materials development, and novel solid-state materials technology communities (emerging compositions, materials synthesis/processing, combinatorial screening/optimization, robust module designs, etc.) regarding the development of next-generation waste heat recovery systems. This request includes input from the researchers, developers and end-users of waste heat recovery technologies, such as power plants, factories, utilities, manufacturers, data centers, and the like. Consistent with the agency’s mission, ARPA-E is seeking clearly disruptive, novel technologies, early in their R&D cycle, and not integration strategies for existing technologies.

Please carefully review the REQUEST FOR INFORMATION GUIDELINES below, and note, in particular, the information you provide will be used by ARPA-E solely for program planning, without attribution. THIS IS A REQUEST FOR INFORMATION ONLY. THIS NOTICE DOES NOT CONSTITUTE A FUNDING OPPORTUNITY ANNOUNCEMENT (FOA). NO FOA EXISTS AT THIS TIME. Respondents shall not include any information in their response to this RFI that might be considered proprietary or confidential.


Waste heat recovery is a significant opportunity – in 2015, 59.2 quadrillion BTU of energy was wasted mainly in the form of heat[1]. Much of the waste heat has been characterized by its source and its temperature, particularly in the transportation and power generation sectors[2], as well as in the industrial sector[3]; only very limited waste heat characterization has been applied to the buildings sector. In total, approximately 71% of all waste heat sources have been well characterized, as shown in Table 1.

Through aggregated analysis of waste heat data from the literature, ARPA-E found that most waste heat (~75%) is low-grade (≤230oC). This temperature regime is not easily converted to usable work as its exergy is roughly a third of the total heat generated (Figure 2); a Carnot analysis yields a maximum efficiency of only ~40% (e.g. 25°C cold-side). A majority of the higher grade waste heat resides in the 230°C to 400°C range. This can be seen in Figure 2, which shows the cumulative percentage of total waste heat as a function of temperature differential. Figure 2 also illustrates the cumulative percent of the total maximum work potential at each temperature difference. The maximum work potential is defined here as the amount of waste heat available at any temperature multiplied by the Carnot efficiency at that temperature. From Figure 2, it can be seen that approximately 85% of work potential from waste heat sources across all sectors in the United States comes from waste heat sources at or below 400°C. Thus, ARPA-E is keenly interested in waste heat conversion in this temperature range.

Several technologies exist to realize the opportunity of lower-grade waste heat recovery, and are typically either mechanical, solid state, or hybrid systems. Examples of mechanical systems include the Organic Rankine cycle, and Kalina cycle, while examples of solid-state devices include thermoelectric generators, piezoelectrics, and multiferroics among others. Mechanical systems are often limited by their complexity, large footprint (e.g. size/mass), and parasitic power requirements. These are particularly challenging limitations for waste heat recovery in the transportation or mobile sectors, where a majority of the opportunity lies (Table 2). Solid-state devices have advantages in mobile applications due to their small footprint and lack of complexity and parasitic power requirement. Unfortunately, existing solid-state technologies have low efficiency and high cost. However, there may exist an opportunity to greatly improve most solid-state technologies.

For example, one might seek to improve the performance per unit cost of a thermoelectric generator (TEG). To date, TEG devices remain very inefficient (<6%) and costly. If their figure of merit for TEGs (ZT, a surrogate for device efficiency), were to be improved from current state-of-the-art values of around 0.8 – 1.4 up to 3, device efficiencies could reach approximately 20%. With that level of performance, if device costs could also drop to $1/W, TEGs could significantly penetrate the waste heat recovery market[1]; this would include a significant portion of the work potential in Table 2. Similar transformative performance and cost goals can be envisioned for the other solid-state waste heat recovery systems.

Thus, ARPA-E is seeking input from the broader research and development community regarding lower grade waste heat recovery systems and, in particular, solid-state recovery opportunities. Since preparing technologies for an eventual transfer from lab to market is a key element of ARPA-E's mission, concepts should eventually be commercializable with reasonable operational systems costs (e.g. $1/watt).

Purpose and Need for Information:

The purpose of this RFI is solely to solicit input for ARPA-E’s consideration to inform the possible formulation of future programs intended to help create transformative waste heat recovery systems. ARPA-E will not provide funding or compensation for any information submitted in response to this RFI, and ARPA-E may use the information submitted to this RFI on a non-attribution basis. This RFI provides the broader research community with an opportunity to contribute their views and opinions regarding the needed development path for waste heat recovery technologies, including energy use and adoption consideration in relevant end-use applications. Based on the input provided to this RFI and other considerations, ARPA-E may decide to issue a Funding Opportunity Agreement (FOA). If a FOA is published, it will be issued under a new FOA number. No FOA exists at this time. Additionally, ARPA-E reserves the right to not issue a FOA in this area.


ARPA-E is not accepting applications for financial assistance or financial incentives under this RFI. Responses to this RFI will not be viewed as any commitment by the respondent to develop or pursue the project or ideas discussed. ARPA-E may decide at a later date to issue a FOA based on consideration of the input received from this RFI. No material submitted for review will be returned and there will be no formal or informal debriefing concerning the review of any submitted material. ARPA-E reserves the right to contact a respondent to request clarification or other information relevant to this RFI. All responses provided will be taken into consideration, but ARPA-E will not respond to individual submissions or publish publicly a compendium of responses. Respondents shall not include any information in the response to this RFI that might be considered proprietary or confidential.

Responses to this RFI should be submitted in PDF format to the email address by 5:00 PM Eastern Time on Friday, September 30th, 2016. ARPA-E will not review or consider comments submitted by other means. All emails should conform to the following guidelines:

  • Please insert "Responses for RFI for FOA DE-FOA-0001607" in the subject line of your email
  • Please include name, title, organization, type of organization (e.g., university, non-governmental organization, small busines, large business, federally funded research and development center (FFRDC), government-owned/government-operated (GOGO), etc.) email address, telephone number, and area of expertise in the body of your email.
  • Responses to this RFI are limited to no more than 10 pages in length (12 point font size).
  • Responders are strongly encouraged to include preliminary results, data, and figures that describe their potential medodologies. However, do not include any information in a response to this RFI that might be considered properietary or confidential.
  • Questions: ARPA-E encourages responses that address any subset of the following questions of relevance to the respondent and encourages the inclusion of references to important supplementary information.


  • Lower Grade Waste Heat Recovery - RFI (Last Updated: 8/15/2016 11:12 AM ET)

Contact Information

    Please submit your comments in PDF format by 5:00 PM Eastern Time on September 30, 2016. ARPA-E will accept responses to this RFI immediately.

Submission Deadlines

  • Concept Paper Submission Deadline: TBD
  • Full Application Submission Deadline: TBD