Repurposing Waste Steam and Hot Water to Accelerate Plant Growth in Heated Green Roofs

Abstract

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.

Thermoelectric Powered Security Systems in Iceland Using a Geothermal Steam Pipe as a Heat Source

“…Therefore, the voltage is additive, but the amperage remains fixed when wired in series. When wired in parallel the amperage increases while the voltage is approximately the average of the units [2,5,6]. Carnot efficiency in this temperature range is 30%.…”

“…The power produced was approximately 6 W using the calculations established in the authors' previous papers [2,5,6]. Figure 3 shows the steady state performance of the generators over 30 days.…”

“…The authors used Laird PB23 Series thermoelectric modules (TEMs) that are commercially marketed as solid-state heat pumps. A temperature difference on opposite sides of the modules produces electricity [2,4]. Thermoelectric modules are voltage sources like photovoltaic cells.…”

“…It has an underground piping system in Iceland that is similar to heated sidewalks in New York City and how waste heat from combined heat and power (CHP) systems warms green roofs [2].…”

Advanced Thermoelectric Materials for Energy Harvesting Applications

“…This can be achieved more precisely via creating proper material "nanostructuring" inducing a large number of interfaces and facilitating thus a phonon scattering resulting into low thermal conductivity values. The TE material's research and the promising nanostructuration approaches are part of the wider field of nanotechnology, where key elements are the long-range ordering with controlled nanostructures for enhanced optical [21][22][23][24][25][26][27][28][29], electrical [30][31][32][33][34][35][36][37][38][39], mechanical [40][41][42] and magnetic [43,44] properties. Figure 3 demonstrates the number of publications on TE materials from 1965 to today, highlighting the slight increase of TE research rate from 1965 to 1993 and the rapid increase from that year to now, due to the flagship stimulating work of Dresselhaus (data collected from Science Direct data library using "thermoelectric" as the keyword).…”