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This paper presents the design, implementation and evaluation of a thermoelectric-based point of use power generation system with no moving parts. The power system was designed to be robust and stable, capable of being clamped onto the outer wall of a hot steam pipe with a temperature of over 160°C using only heat pipes and natural convection of ambient air for cooling. Several systems were built and tested. One system was built and tested at the Cooper Union in New York City. The power generation was evaluated for different ambient and steam pipe temperatures. The other systems were attached to an 85°C geothermal hot water pipe and a 100–120°C geothermal steam pipe in Iceland. The Cooper Union system was used to power two microcontroller based security cameras, one with wireless LAN and another with cellular connectivity. Additional testing of the PV voltage controller and the generator were conducted in Iceland. The results show that the system can be used to power surveillance systems, even in remote locations without access to the electrical grid. Because the system does not require grid access, it will run constantly, and hence improve security. Furthermore, the unit’s power generation is greater in colder environments that substantially degrade battery performance.

Municipal steam district heating services such as New York City’s Consolidated Edison’s have no recirculation system. The waste heat, usually in the form of steam condensate and hot water, is mixed with and cooled by municipal potable water. Since 2006, The Center for Innovation and Applied Technology and The Laboratory for Energy Reclamation and Innovation at the Cooper Union have been developing a system to use this thermal pollution to heat the growth medium of green roofs. The authors have also constructed three geothermal heated gardens systems in Iceland. American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE) specifications for heated sidewalks were referenced in all locations. The heated green roofs have the potential to save more than 2,000,000 cubic meters of potable water if applied to 40% of Consolidated Edison’s steam customers. Plant growth is often accelerated by 20% or more in all locations.

In Iceland there is a super abundance of waste hot water from geothermal power plants. Some of this is re-purposed (sequentially used) for district heating and heated swimming pools. This vast underused energy source can also enable the growth of out of zone plants, enhance agricultural production by 20% and extend the growing season. The authors have developed and field tested an energy intensive shallow system of bottom heat using the existing heated sidewalk materials. Tomatoes that do not survive outdoors in Iceland have produced ripe fruit. A zucchinis harvest was documented and the test banana plant was still alive in September after the first frost. These plants all died in the control garden which had the same piping system, and identical soil types and depths. Heat transfer data, infrared analysis and plant growth data were gathered to preliminarily document and quantify the system’s viability and market potentials.

Existing elevator systems are upgraded approximately every 20 years, providing an opportunity for energy reduction upgrades. This demands complicated analysis because elevators consume energy while at idle and in lifting modes. Traffic patterns, loads and building usage must also be considered in addition to energy recovering potentials. An objective and inclusive measurement methodology for measuring elevator energy efficiency is essential for a valid cost benefit analysis. The necessary requirements for a workable system and a usable first generation solution are presented.