Harry Zvi Tabor

Harry Zvi Tabor was born in London on March 7, 1917.[1][3] He was educated at Quintin Hogg School in London, then studied physics at London University, earning a bachelor's degree while working in industry.[1][4] He later completed doctoral studies in renewable energy at the Hebrew University of Jerusalem.[2]

During World War II, Tabor worked as a research physicist on defense projects.[1] His engagement with the future state of Israel began in 1946, when he was active in the Zionist movement in England and met David Ben-Gurion's scientific secretary, with whom he discussed the importance of science to the country being built and its lack of natural resources.[6] Before his immigration, he also helped convert cargo ships into passenger vessels for Jewish immigrants.[2]

Tabor immigrated to Israel in 1949 after Ben-Gurion's office offered him a position.[4] He joined the physics and engineering desk of the Research Council of Israel and was tasked with establishing Israel's National Physical Laboratory, which he built from a small team of roughly four to six employees.[7][6] He served as the laboratory's director from 1950 to 1974 and simultaneously served on the Research Council of Israel from 1949 to 1974.[1] He also worked at the Prime Minister's Office and established the Scientific Research Foundation, known as SRA, after arguing that a government department was unsuitable for dynamic research. He recruited an initial staff for the new body.[6][8]

Tabor served on international committees including UNESCO and was president of the International Solar Energy Society from 1981 to 1983.[1] In 1961, he was listed as a rapporteur for the United Nations Conference on New Sources of Energy in Rome, representing the National Physical Laboratory of Israel, based at the Danziger Building, Hebrew University, Jerusalem.[9]

Tabor entered solar-energy research because Israel lacked natural resources and the Prime Minister's Office had received public requests asking why the country was not harnessing the sun.[6] Studying Israel's existing rooftop solar water heaters — essentially black plates, water pipes, and glass copied inefficiently from foreign designs — he concluded that their efficiency could be doubled without increasing their size.[4][6]

His solution was a selective surface: a coating that maximized the absorption of sunlight while minimizing heat re-emission. He described the insight as "a trick in physics" by which radiation loss could be reduced by a factor of approximately six, making convection the dominant loss and immediately doubling collector efficiency.[4] His laboratory found a workable solution within two months.[6] In 1955, Tabor developed a black coating for absorbing solar radiation that became a foundational breakthrough in Israeli solar technology; his surfaces were later incorporated into solar water heaters.[2] Tabor registered the solar-water-heater patent in the name of the State of Israel and received no personal payment from it.[8]

The selective surface was adopted by solar-collector manufacturers globally, and Tabor stated that practically all solar collectors worldwide came to use surfaces developed by his team.[4] His technology was used in non-photovoltaic solar applications, including by Luz and BrightSource Energy in early large-scale solar power stations in the United States.[4] Israel subsequently required solar collectors on newly constructed buildings, a law that Tabor said saved several million tons of fuel annually.[6] The technology eventually reached an estimated 95% of Israeli homes and was credited with saving a significant share of the country's electricity consumption.[8]

In 1955, Ben-Gurion urged Tabor to bring a new solar collector to an international conference on solar energy in Arizona. His team built and transported the device in roughly a month, and Tabor later recalled it was "the hit of the conference" and said it put Israel on the map in the field.[6]

Working with engineer Yehuda Bronicki in the late 1950s, Tabor developed a small solar-powered turbine intended for use in developing countries and remote areas far from electricity grids.[6] They presented it in 1958 at a United Nations international conference on small power units.[6] A 1961 demonstration brought a collector and turbine to a UN conference in Rome, but Tabor recalled there were no buyers at the time.[4]

The Bronicki family began manufacturing the turbine at a leather-renewal factory in Yavne, and after years of development the technology found its most successful application in geothermal energy. Tabor said it enabled electricity generation at lower temperatures than conventional installations and that Ormat — the company Bronicki founded — eventually captured approximately 70% of the global market for low-temperature geothermal stations.[6] Tabor described the turbine as simpler to maintain than an engine, a quality particularly valuable in locations without trained maintenance personnel.[4]

In the 1970s, Tabor developed an electric vehicle, motivated by the large share of Israel's energy budget consumed by transportation and his goal of applying solar-derived energy to mobility.[6] He fitted the vehicle with a small flywheel — weighing approximately five percent of the car's mass — to give it acceleration comparable to a conventional automobile.[2][6] He presented the vehicle at an international exhibition in Düsseldorf, Germany, where it competed directly with entries from General Motors and other large manufacturers, and Tabor recalled it received considerable attention.[2] Despite positive reception, the project was not commercially adopted; Tabor also recalled that he built a hybrid benzene-electric car in the same era but could not find buyers when oil cost just $5 a barrel, and that car companies were unwilling to invest in charging infrastructure.[4]

Tabor also proposed a solar pond for generating electricity. A demonstration model was built and successfully showed viability, but was ultimately discontinued.[4]

Tabor received the Weizmann Prize for Exact Sciences in 1956, awarded for his work integrating the selective-surface technology with a water boiler to create the modern solar water heater.[5] He also received a prize from Prime Minister David Ben-Gurion.[2] In 1975, the Royal Society of London awarded him its Gold Medal Energy Award.[1]

In 1995, the Israeli Knesset presented him with its Quality of Life Award.[1] In 2014, President Shimon Peres awarded Tabor the Presidential Medal of Distinction, recognizing him as a symbol of Israeli innovation and for inspiring scientists and entrepreneurs in solar energy.[5] He was named Person of the Year at the 2015 Energy and Business Conference in the weeks before his death.[2]

Harry Zvi Tabor died in Jerusalem on December 15, 2015, at the age of 98.[2] His work transformed solar water heating in Israel from an inefficient novelty into a national standard, and his selective-surface technology shaped solar-collector design on a global scale.[4][8] Through his collaboration with Yehuda Bronicki, his turbine research gave rise to Ormat Technologies and its dominant position in the geothermal energy market.[6] His brother David Tabor was also a prominent physicist, known for his research into friction and wear between solid surfaces.[10]

Tabor arrived in Israel committed to the Zionist project of building a resource-poor state through science, and he channeled that conviction into decades of applied research that produced technologies still in widespread use long after his death.[6][8] The Israeli government's recognition of him as a symbol of innovation reflects both the practical impact of his inventions and the broader significance of solar energy to Israel's national development.[5]