OVERVIEW A complete, internally consistent paper design — nothing has been built — for a heat-driven desiccant comfort and drinking-water platform for humid-tropical climates, deployable on land and on marine platforms. Input is solar thermal or waste heat at 60–93 °C; outputs are dry cool air, safe indoor air quality (<1,000 ppm CO2 in sealed operation), hot water, and potable water, for occupied volumes of roughly 100 m3 (yacht interiors, small dwellings, cabins, shelters). The sole governing design point is DP-A: 32 °C / 80% RH (humidity ratio 24.2 g/kg, dew point 28.1 °C) with a raw-water sink near 29 °C. At this condition every ambient heat sink sits at or above the dew point, so sink-cooled condensation harvests essentially no water and evaporative cooling — including dew-point (Maisotsenko-cycle) indirect evaporative coolers — cannot cool below the dew-point floor. Only a desiccant breaks that floor, because its surface vapor pressure is set by concentration or loading rather than by a cold sink. The consequential hard problem is regeneration against near-saturated surroundings, not capture — an inversion of the arid-climate sorbent-harvesting literature that drives every design decision. The platform integrates two complementary desiccant tracks on shared infrastructure (M-cycle, water loops, thermal bus, controls): (1) Liquid track — calcium chloride (CaCl2) brine in film contactors with sealed-still regeneration: dehumidification to ~55% RH, berth spot cooling, moisture and CO2 storage batteries, 8–18 L/day distillate, 25–80 W electrical draw, ~9–11 kWh/day of heat at 60–93 °C from any source including small solar collectors. (2) Solid track — aluminum fumarate MOF (MIL-53(Al)-FA / Basolite A520 class) desiccant-coated heat exchanger (DCHX) on a ~10-minute thermal swing: genuine full air-conditioning (~17–18 °C supply, ~3.5 kW sensible), ~50–70 L/day potable water surplus, water-neutral operation in every ambient, driven by ~7.5–9 kW of continuous 60–65 °C waste heat. Supporting doctrines include exhaust-vapor recovery into distillation, mixed-mode ventilation with a hard CO2 interlock and ERV latent recovery, a two-bed solid-amine thermal-swing CO2 battery for sealed operation, humidification-dehumidification (HDH) desalination integration, and two-worlds chloride materials rules applied regardless of site. All sizing claims are confidence-graded and gated on an explicit low-cost bench validation program. Findings are recorded as X1–X10 and corrections as F-seriesentries in a findings register. The repository contains the full document lineage (docs 00–50), diagram set, rendered PDF set, and the render pipeline. DEFENSIVE PUBLICATION NOTICE This work is published as a deliberate public disclosure intended to constitute prior art under 35 U.S.C. § 102 and corresponding provisions worldwide. No patent protection is sought or held by the authors for any subject matter disclosed herein, and the authors intend this dated public record to preclude the patenting of the disclosed subject matter by any party. LICENSING Tri-licensed open publication: hardware designs and specifications under CERN-OHL-P v2; documentation and diagrams under CC-BY-4.0 (the record-level license shown here); scripts and code under MIT. See LICENSE.md in the repository for the scope map. TERMINOLOGY AND MATERIAL ALIASES (for search) Liquid desiccant air conditioning (LDAC); liquid desiccant dehumidification; calcium chloride / CaCl2 brine; aluminum fumarate / aluminium fumarate / MIL-53(Al)-FA / Basolite A520; metal-organic framework (MOF); desiccant-coated heat exchanger (DCHX); desiccant wheel alternative; Maisotsenko cycle / M-cycle / dew-point indirect evaporative cooling; atmospheric water harvesting / atmospheric water generation; humidification-dehumidification (HDH) desalination; thermal swing adsorption; solid amine CO2 scrubbing (Lewatit VP OC 1065 class); enthalpy/energy recovery ventilator (ERV); solar thermal regeneration; evacuated tube collector; waste heat recovery; marine HVAC; shipboard air conditioning; off-grid cooling; humid tropical climate. RELEVANT CPC CLASSIFICATIONS (verified July 2026) F24F 3/14 (air treatment by humidification/dehumidification); F24F 3/1411 (dehumidification by absorbing or adsorbing water, hygroscopic desiccant); F24F 3/1417 (liquid hygroscopic desiccants); F24F 5/0035 (cooling using evaporation); B01D 53/26 (drying of gases or vapours); B01D 53/28 (selection of substances as sorbents); C02F 1/04 (water treatment by distillation); B63J (auxiliaries on vessels).
Ramon Pla (Sat,) studied this question.