Harry Zvi Tabor lives on Rehov Hameyasdim (Founders Street) in Jerusalem, which is quite apt. As the father of the local solar energy industry, he began more than 50 years ago what is only really coming to fruition today. At 91, Tabor is remarkably spry, "though I've slowed down a lot since 81," he remarked to The Jerusalem Post. Nevertheless, he popped up and down repeatedly to retrieve mementos from the other room and make copies of documents. His wit is dry and his perspective both appreciative and forgiving. Although "officially" retired since his 70s, Tabor is still tinkering with solar energy ideas. His latest - how to make solar power stations more cheaply. When pressed to reveal how they could, he quickly replied "You can't ask me to give away all my secrets." Although you may not have heard of Tabor, if you live here you doubtless use a product he was instrumental in developing - the dud shemesh or solar water heater that 95 percent of houses in the country have, according to National Infrastructure Minister Binyamin Ben-Eliezer. However, if the minister has his way, everyone will have heard of Tabor shortly. A few weeks ago, he proposed him for an Israel Prize for his contributions. Tabor is self-deprecating about his achievements, referring to physics breakthroughs as "a physics trick" and continuously underscoring the role luck played in his inventions. He is most proud of making his discoveries while in the service of the state and thus putting Israel on the solar map years ago. The highlight film of discoveries is rather impressive - a surface which absorbs the sun's rays much more efficiently. It is known today as a Tabor surface and is used in much of contemporary's non-photovoltaic solar technology, including Luz's and Brightsource Energy/Luz II's technology. He developed a solar powered turbine in the 1960s with Yehuda Bronicki, who later utilized the idea in conjunction with geothermal energy. Bronicki went on to found Ormat and today it is a world leader in building geothermal power plants. Bronicki was enthusiastically behind the idea of granting Tabor an Israel Prize, he told the Post last week. Tabor also built a hybrid benzene/electric car in the 1970s, but couldn't find any takers because oil was just $5 a barrel. Exactly 25 years later, GM and Toyota put their hybrids on the market. He also came up with the idea of a solar pond to generate electricity, but a demonstration model was discontinued after it was proven viable. A career civil servant, Tabor is wise to the ways of politicians and their frequently inconstant support for projects that might not come to fruition for years or even decades. While occasionally bitter over other civil servants' narrow-mindedness, he is too realistic to hold grudges against the political system. TABOR WAS born in London in 1917. He got his bachelor's degree in physics from London University while working in industry. "My brothers all went to school, but I decided to go into industry," he explained. It was exactly that combination of practical experience and studies that brought him to the attention of prime minister David Ben-Gurion, who sent a letter to England to offer Tabor a job in 1949. "I had decided that I was coming to Israel without an offer and 10 days before I left England I get a letter from Ben-Gurion's office saying they are offering me a job. So that made life very easy," Tabor recalled. "He knew about me because... during the Mandate there was a thing called the Board of Scientific and Industrial Research whose purpose was to exploit the scientific competence of the Jews to improve industry in Palestine. Ben-Gurion had his eye on this and the secretary of this board was a disciple, if you like, of Ben-Gurion, and he met me in England, so he knew about me. So when he got back to Israel - that was just before the state was formed - and after the state was formed, he said, 'Oh, we've got a physicist.' "He was interested in me because he was a professor of physics and in those days students of physicists were all academics, they didn't have any industrial experience. So when he heard of a Jewish Zionist physicist who had practical experience, he put his hand on him." Tabor was not brought here initially to do solar energy research. Instead, as part of a department called Encouraging Industrial Development in the New State of Israel, he was assigned the task of creating the National Physical Laboratory. Tabor had originally suggested the idea to the secretary of the board in previous discussions. "Listen, I told him, Palestine has three systems of measurement, it has metric, it has British and it even has Ottoman - they measure things in okers or whatever it is, and that's not for a modern country. You have to have one system. So he took this message that you had to have the equivalent of the English National Physical Laboratory that fixes the standards that decides what is the meter, the kilogram, what is the hour and so on. So when I came to Israel, they said, okay, you set up a national physical laboratory for the same purpose, which I did," Tabor recounted. Once he had a laboratory, he was quick to perceive the R&D possibilities. He started thinking about solar energy, "and that's how I got into the industry." "I chose the area of solar energy for two reasons: First of all, Israel had no energy supplies - no coal and no oil. In those days, we weren't so worried about the embargo of the Arabs, but nevertheless we didn't have it. We had to buy all the fuel. And nobody worried about ecology in those days. "When I came I found a small number of solar water heaters, a very small number, a handful. They were very bad copies of what had been made abroad. And I took a look at them as a physicist and I found that it was possible to double the efficiency of the thing without making it any bigger and that converted it from an unpopular sort of rare phenomenon to something that was bought by a lot of people. "Now I had luck because I made a development which no plumber could make. A physicist could make it because it required a special knowledge of physics. Simple physics, but nevertheless. Because of this thing called a selective surface, it has been taken up by everyone who makes solar collectors. All solar collectors in the world today, practically, use the selective surfaces that we developed." For a man of Tabor's advanced years, photovoltaics, though now more than 75 years old, is still the new kid on the block. "In those days, the only way of harnessing solar energy was by means of a solar collector. There was no PV. Photovoltaics was only invented in 1928 or 1924 or something like that, so in those days when I was working on it, it was almost nonexistent and terribly expensive. So the only PV that was used then was for photo exposures or traffic signals but not for producing energy, so I didn't have any competition from photovoltaics," Tabor said. He explained in layman's terms the two breakthroughs that put him and Israel on the global solar map. "When a body is heated, it radiates energy. And if you have a collector, which is a black plate with a sheet of glass over it to prevent it being cooled by the wind, the black plate is heated by the sun and then it radiates heat to the glass cover. It also loses energy by convection because the air inside between the surface and the plate circulates. But the big item was what's called the radiation loss. "Now I found a trick in physics whereby the radiation loss could be reduced by a factor of about six. When I did that, the convection loss became the dominant loss and not the radiation loss. In other words, immediately the collector was twice as efficient. The big step forward then was you could make what's called an evacuated collector. Why? If you reduce the radiation loss by six, if you take the air out, the improvement is very large indeed." Thirty years later, "this led to the opening up of the first solar power stations made in the US by the Luz company. They used my selective surface and that made it feasible. These were the first major watt solar power stations in the world." ORIGINALLY PLANNING to turn solar into a cheap energy source for developing countries, Tabor said he was rudely awakened to reality when there were no takers. "Everyone in the solar energy business fooled themselves that if the developing countries had cheap solar energy, they would take it up. But that didn't happen for two reasons: They had no money and they expected somebody else to take it up for them. I am not criticizing them, I am just stating an historical fact." Whether a fluke of timing or inevitability, Tabor's solar water heater made Israel's reputation 53 years ago. "When we demonstrated the first collector, we had another bit of luck. It was a month before the first solar world conference. In 1955, the people of America and Australia organized a conference. This was about a month after I had developed the collector. So Ben-Gurion said, 'You had better go to the conference and take the collector with you.' So we had to work very hard for a month to get the collector ready. "It was the hit of the conference because it was the only solar device that was new in concept. All the others were classical and followed what everyone else had done. But I'd introduced a new principle and so it made a big impression and it put Israel, and myself, on the map as far as solar energy was concerned. "The use of thermal heaters to produce hot water was encouraged in the 1960s and '70s. And it was made into a law for all new houses in 1980. It saves 4% of petrol consumption, which is not inconsiderable for one little item." Not content to stop there, Tabor began work on a solar powered turbine. "My second major contribution was to develop a turbine instead of an engine. It's much simpler because it just has one wheel that goes round. I was thinking of the developing countries where they have no maintenance people. Second, there were some thermodynamic tricks where we could make a small turbine as efficient as a large one, which was very unusual. So the result was we had a turbine we could demonstrate. We shipped out a collector and turbine to Rome" in 1961 to a UN conference on new sources of energy. Again, Tabor's hopes that the developing countries would buy the new steam turbine were unrealized. "Here we had a very efficient, very simple turbine. And no clients. Then there was another piece of luck. A young scientist named Yehuda Bronicki from France was interested in making aliya and had written his master's thesis on turbines. So I grabbed him. This gentleman and I made a marvelous team and resulted in the formation of what is today known as the Ormat company, one of the most successful companies in Israel. It is not profitable because of me but because of my partner." What happened was, this young man, Bronicki was very disappointed when there were no takers for the turbine, Tabor explained. So his father, having a lot of faith in him, said he would support him. His father said he would build him a factory on a plot in Yavne. "He worked for six years until he had a perfect product to sell. Once he had a product then he was all set because he had a product the world needed," Tabor said. Shifting slightly, Bronicki focused on geo-thermal energy rather than solar energy to run the turbine he had created. Today, Ormat has built the second largest number of geo-thermal plants in the world. FROM COLLECTING solar energy, Tabor quickly turned to practical applications for it. "It was clear to me as it is clear to people today. Even if you could harness solar energy for electricity that was only a minor part of our energy consumption. A big item of our energy consumption is in transport. So I thought how do you use solar energy for transport? Well you can't put a solar collector on the roof because it would have to be so big that it would be impossible. So the only way to exploit solar energy for transport is to convert the solar energy to electricity. And then use the electricity to drive an electric vehicle. So I was tempted to go into the electric vehicle business." This was a quarter century before the first hybrid vehicles drove off the assembly lines. "It's very interesting that in a little country like Israel we produced a new kind of electric vehicle which was exhibited in an international conference. The reason we chose a van was because it was much easier to convert than a private car. I'm very proud of it although it has no practical significance at this moment. "But the car companies were anti-electric; they threw us out at the door. If the car companies had to go into electric cars, they would need an enormous capital investment in charging stations and equipment. It is only recently that this has started to happen. Exactly 25 years after I demonstrated this, almost the same week, Toyota and GM came out with a hybrid vehicle." Showing a clear grasp of current trends, Tabor analyzed Better Place CEO Shai Agassi's foray into electric cars. "Agassi is doing what the car companies should have done - making the investment in the charging stations and the other facilities and putting up the capital. To build a different kind of car is an expensive business. It's ridiculous for a little country like Israel to try to go into the car business in competition with Toyota, and I didn't attempt it. But he is willing to do it because he has got capitalists and they are spending a lot of money and the pressure from the ecologists is giving him encouragement. You didn't have it a few years ago." Tabor thinks it is just a matter of time before the electric car industry takes off. As more and more companies get in on the act, competition will force prices to drop. Similarly, Tabor is cautiously optimistic about the future of photovoltaics. The real advance is in PV, he said, because you generate electricity directly from the sun [as opposed to creating steam to power a turbine]. It'll take some time though for the price of photocells to come down and the efficiency to go up. "What is really needed is some evolutionary concept in photovoltaics to increase efficiency. Cells are not very efficient now, 10%, maybe 12%. Some physicist makes them 40% efficient then he's in business. But that's not going to happen tomorrow because people have been working very hard on this for a long time and they've only slowly increased efficiency of the cells." For himself, Tabor has been examining how to make solar power stations more cheaply. "I retired about 20 years ago from my work and a year ago my colleague in Ormat said to me why don't you return to solar energy. If I make a suggestion to him, he'll try it out. I'm working now on lower cost solar power stations. If you can reduce the price of power stations people will build a lot more of them." He refused to disclose any details: "Don't ask me to give away my secrets. It's nice for me to have a responsible company to judge my ideas. If I make a silly suggestion, they'll tell me." On being nominated for the Israel Prize: "I was very surprised. Well, I've had a few prizes, mostly international prizes. Naturally I'm pleased. But the real thing that pleased me was it was the first time a minister said energy was important. Up to now, the ministers had other things to worry about."
