raw · articles · ingested 2026-06-30
Direct Use of the Sun's Energy
Source: Steve Baer / Zomeworks archive
Author: Farrington Daniels, Solar Energy Laboratory, Engineering Experiment Station, University of Wisconsin
Publisher: Yale University Press, New Haven, CT
Date: 1964 (copyright; preface dated January 1964, Madison, Wisconsin). Third printing, 1971 (this copy).
Library of Congress: 64-20913
ISBN: 0-300-0399-4
Pages: 391 (confirmed from physical copy in Joule Heist collection, ISBN 978-0-300029-86-4, 3rd printing 1971; ToC ends at p. 288 but full book includes index and back matter)
Funding: Rockefeller Foundation (9 years at U. Wisconsin); Guggenheim Foundation (earlier phases)
Series: “Trends in Science” — a project of the Yale Chapter of Sigma Xi and Yale University Press
PDF: 72.3MB, image-based; read in ≤20-page batches
Summary
Survey of solar energy science for researchers and engineers, expanded from Sigma Xi lectures at Yale (1960) and an earlier lecture (1951). Daniels visited scientists in non-industrialized countries to understand their solar energy needs; the book is oriented toward practical, low-cost applications accessible in small laboratories without expensive equipment.
The foreword by George A. Baitsell (February 1964) frames solar energy as a survival problem: “for the stored fuels, fossilized or organic, are being consumed at an incredible rate.” Daniels had been working on the problem for a decade.
This is the canonical pre-oil-crisis solar science text — the scientific establishment’s view of solar energy the year Holly Baer made the first zonohedra model in Zurich.
Table of Contents
| Chapter | Title | Pages | Relevance to archive |
|---|---|---|---|
| 1 | Introduction + General Bibliography | 1 | Context |
| 2 | History: Early Experiments, Solar Symposia, Solar Energy Society | 6 | Pre-Baer lineage |
| 3 | Solar Radiation: Variations, Measuring Instruments, Geographical Distribution | 15 | Physics foundation |
| 4 | Collectors of Solar Radiation: Flat-Plate, Focusing, Mountings, Materials | 36 | Collector theory |
| 5 | Cooking: Boiling, Baking, Field Tests, Simple Solar Cooker | 63 | Low-tech applications |
| 6 | Heating Water: Types, Simple Heater, Boiling | 74 | Solar water heating |
| 7 | Agricultural and Industrial Drying | 89 | — |
| 8 | Storage of Heat: by Heat Capacity, Physical Chemical, Two-Vessel, Water Ponds | 97 | Ch 8.4 = predecessor to Hay’s Skytherm |
| 9 | Heating Buildings: Space-Heating Systems, Requirements, Tests, Architectural Problems, Heat Pumps, Small Units | 106 | Building heating |
| 10 | Distillation of Water | 118 | — |
| 11 | Solar Furnaces | 139 | — |
| 12 | Selective Radiation Surfaces: Experimental, Theoretical, Particulate Coatings | 152 | Directly relevant to unglazed collector efficiency |
| 13 | Cooling and Refrigeration: Absorption-Desorption, Refrigeration, Air Conditioning | 164 | Passive cooling physics |
| 14 | Heat Engines: Solar Engines, Steam, Hot-Air, Vapor, Economics | 178 | Baer’s gravity engines echo this |
| 15 | Thermoelectric and Thermionic Conversion | 197 | — |
| 16 | Photovoltaic Conversion | 206 | — |
| 17 | Photochemical Conversion | 215 | — |
| 18 | Storage and Transportation of Power: Mechanical, Fuel Cells, Hydrogen Fuel | 234 | — |
| 19 | Conclusions | 248 | — |
| — | Bibliography | 261 | — |
| — | Todo List | 288 | — |
Key chapters for the archive
Ch 8.4 — Water Ponds (p. 104)
Tabor’s salt-gradient solar ponds (1 m deep, Dead Sea brine layer) for heat storage and power generation. Not the same as Hay’s Skytherm — these are heat collection/storage ponds, not cooling roof ponds. The brine gradient prevents convective mixing; bottom temperature approaches boiling. Coils at bottom give low-pressure steam for turbines. Key reference: Tabor, H., “Large Area Solar Collectors (Solar Ponds) for Power Production,” UN Conference on New Sources of Energy, 1961; Solar Energy 7:189–94, 1963.
Ch 9 — Heating Buildings (p. 106)
Surveys solar houses as of 1961 UN Conference. Fewer than 20 solar-heated buildings in the world; all between 35°N–42°N. Key references from the 1961 UN Conference include:
- Bliss, R., Jr. — “Performance of an Experimental System Using Solar Energy for Heating and Night Radiation for Cooling a Building” (footnote 170). Solar collector in Arizona; unglazed flat-plate.
- Thomason, H. — “Solar Space Heating, Water Heating, Cooling in the Thomason Home” (footnote 174). The same Harry Thomason cited by Hay and Baer as a “creative activist.”
- Yanagimachi, M. (1958) — “How to Combine Solar Energy, Nocturnal Radiation Cooling, Radiant Panel System of Heating and Cooling, and Heat Pump to Make a Complete Year Round Air-Conditioning System.” Transactions of the Conference on the Use of Solar Energy: The Scientific Basis, 3(2):21–31. Tucson, 1958. (footnote 175) — the Baer/Cool Cell concept, articulated in 1958.
Daniels explicitly notes the dual-use opportunity (p. 9.2): “Another area where solar house heating may become important is where both solar heating and solar cooling can be accomplished with the same equipment.”
Ch 12 — Selective Radiation Surfaces (p. 152)
Experimental and theoretical work on surfaces with high absorptivity for shortwave solar radiation but low emissivity in the infrared. Key researcher: H. Tabor (recurring references). Directly relevant to unglazed collector efficiency — a selective surface absorbs solar energy without reradiating it as efficiently. The same surface physics underlies both solar collection and nocturnal radiation cooling. Compile pending for full chapter content.
Ch 13 — Cooling and Refrigeration (p. 164)
The critical section for the Lemon Wiki. Most of the chapter covers absorption-desorption cooling (ammonia systems, etc.) — not directly relevant. But §13.3 contains the key passage:
“Important cooling of houses can be achieved in hot clear climates by radiation to the sky during the night. This may amount to 10 to 35 BTU ft⁻² hr⁻¹, and more. In the desert of north Chile it is possible to freeze water by this means when the air temperature is far above freezing.”
“Bliss has made use of this nocturnal radiation in a house in Arizona, with a black cloth radiator 280 ft² in area. The ‘cold’ amounting to 120,000 BTU was stored in a 10-ton pile of rocks buried in the ground. The cooling was equivalent to about 2 tons of refrigeration.”
“In many areas it is possible to use a solar collector and heat storage for both heating in winter and cooling in summer. Solar collectors for heating should be covered with glass plates or materials that transmit solar radiation and absorb radiation in the far infrared; but the collectors should be uncovered when they are to be used for cooling by nocturnal radiation.”
Unit conversion: 10–35 BTU/ft²/hr = 2.9–10.3 W/ft² — consistent with Baer’s heated-vs-unheated-plates finding of “night radiation exceeds 9.5 W/ft²” (Stickney & Baer, 2002). The same physical phenomenon, measured with 38 years of separation.
Also from §13.1 opening: “Cooling can be produced by storing ‘cold’ from the cooler night air and in some areas by radiation to the night sky.”
The Yanagimachi 1958 reference (footnote 175 in Ch. 9 references) is the earliest known proposal to combine solar + nocturnal radiation + radiant panel + heat pump as a unified year-round system — the conceptual ancestor of the Cool Cell.
Source note
The elib markdown output is available at:
~/Projects/elib-direct-use-of-the-suns-energy/output/markdown/direct_use_of_the_sun_s_energy.md (3,821 lines, searchable). Use grep -n for targeted lookups.
Relationship to the archive
Daniels represents the scientific mainstream that preceded the countercultural solar work of the late 1960s. His framework:
- Institution-funded (Rockefeller, Guggenheim)
- Laboratory-based, empirical
- International in scope (India, Latin America, Africa)
- Physics-first, applications second
Baer’s approach was the opposite: applications-first, no-grant, built with hands. But the physics Daniels documented — water ponds (8.4), selective surfaces (12), passive cooling (13) — is exactly the physics Hay and Baer later built products around. Hay’s 1967 Skytherm can be read as a direct implementation of what Daniels described in Ch. 8.4.
The book was published January 1964 — the same month Baer enrolled at ETH Zurich, and roughly the same time Holly Baer made the first rhombus-icoso-dodecahedron on her grandmother’s attic floor in Zurich.
Compile status
- Registered: 2026-05-14
- Chapters 1–3, 8 (ToC), 12–13 (ToC): Identified — compile pending
- Full text requires reading in batches (72.3MB image PDF). Priority: Ch 8.4 (Water Ponds), Ch 12 (Selective Surfaces), Ch 13.3 (Air Conditioning).