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Title: Energy scavenging from ultra-low temperature gradients
Thermal energy harvesting from natural resources and waste heat is becoming critical due to ever-increasing environmental concerns. However, so far, available thermal energy harvesting technologies have only been able to generate electricity from large temperature gradients. Here, we report a fundamental breakthrough in low-grade thermal energy harvesting and demonstrate a device based on the thermomagnetic effect that uses ambient conditions as the heat sink and operates from a heat source at temperatures as low as 24 °C. This concept can convert temperature gradients as low as 2 °C into electricity while operating near room temperature. The device is found to exhibit a power density (power per unit volume of active material) of 105 μW cm −3 at a temperature difference of 2 °C, which increases to 465 μW cm −3 at a temperature difference of 10 °C. The power density increases by 2.5 times in the presence of wind with a speed of 2.0 m s −1 . This advancement in thermal energy harvesting technology will have a transformative effect on renewable energy generation and in reducing global warming.  more » « less
Award ID(s):
1738689
PAR ID:
10098924
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Energy & Environmental Science
Volume:
12
Issue:
3
ISSN:
1754-5692
Page Range / eLocation ID:
1008 to 1018
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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