“Light From Sweepings”

Lord Kelvin reports on a new method to turn garbage into energy.

The following is a recount of part of an address by Lord Kelvin given at the opening ceremonies of a plant in the vestry of Shoreditch for burning up street sweepings and converting the power thus obtained into electricity (originally from the Daily Telegraph, quoted in the Brooklyn Daily Eagle, July 18, 1897):



The Dust of the Streets Utilized as Fuel for a Municipal Electric Light Factory, From Which Power Is Rented. A Solution of the Street Cleaning Problem.


Lord Kelvin presided at the opening ceremonies and made an address, in the course of which he said, quoting the Telegraph's report:

"It was a remarkable example of the combination of scientific knowledge and forethought with mechanical and engineering skill and with courage in entering upon new undertakings. ('Hear, hear.') It was courage which did not belong to the class of gambling adventure, but the courage to bring into practice carefully worked out engineering results and capabilities. ('Hear, hear.') Shoreditch might well be proud of what its vestry had done for it. It was the premier body to undertake a large work like that they had just seen. Tentative efforts at the furnace method of destroying dust had been made, but little or nothing had been accomplished in the way of getting up steam from the heat developed. The Shorditch electric lighting commenced with dust and the contractors undertook to give 120,000 tons of steam per annum from this source. No doubt more would yet be done. He believed people were only at the beginning of a vast advance in the direction in which the vestry was moving. He believed that unless the neighboring vestries were very quick in following the example that had been set them, people would soon begin to bring their dust to Shoreditch and Shoreditch would make light and power out of it. (Cheers.) Especially power, because he thought at the price suggested a great deal of the work now done by small gas engines would soon be done by electric motors, whose power would be derived from dust. At the price fixed by the vestry he believed that the people of Shoreditch might speedily enter upon the employment of electricity, and they would find it less costly than gas at 2 shillings 10 pence per 1,000 cubic feet."

Lord Kelvin later traveled to the Americas to spread the good news. The New York Times, August 14, 1897, p. 10 (parts unrelated to Lord Kelvin removed, full version here):


Lord Kelvin and the Marquis Ito Among a Long List of Passengers.

[...] British Scientist Talks of Garbage and Its Value.

The steamer Campania of the Cunard Line arrived yesterday, with one of the largest passenger lists of the season. There were 246 first cabin, 296 second cabin, and 391 steerage passengers. A large crowd assembled at Pier 40, North River, to see the liner dock, and to catch a glimpse of two notables on board, each of international fame, though of widely different spheres of activity. They were Lord Kelvin, better known to the scientific world as Sir William Thomson, and Marquise Ito, the Japanese statesman and guiding spirit of the lat Japan-Chinese war.

As the Campania approached her dock, Lord Kelvin and his wife were seen standing on the Captain's bridge, the only passengers allowed on that sanctum. The few persons on the pier who recognized the slight figure and the venerable face, almost hidden from view by a large black hat, sent up a ringing cheer and waved their hats. Lord Kelvin seemed to think the greeting was intended for some one else, notwithstanding the fact that all eyes were directed at him, and looked entirely unconcerned.

He walked down the gangway with his wife, and only when he stood on terra firma, surrounded by a number of admirers, did he realize that he was the centre of attraction. Then a deep glow suffused his face, and he sought shelter. He was seen later, and talked freely on a subject that has engrossed his attention and that of the most eminent scientists both in this country and abroad.

It is the discovery of the means of extracting heat and light sufficient to run electric and steam plants from garbage—a discovery destined, according to Lord Kelvin, to revolutionize the economic policy of all civilized municipalities.

A Talk with Lord Kelvin.

"Millions of dollars," he said, "are thrown away by cities every year in disposing of their garbage and dumping it in places where it only too frequently becomes a menace to life and health, when, if properly handled, it is as good as coal or any other fuel. Where the latest scientific discoveries are applied, a city can save itself the purchase of thousands upon thousands of dollars' worth of coal, and utilize the ashes, cinders, refuse, and discarded food for exactly the same purpose.

"Ten tons of garbage are equal to one ton of coal. Cinders, generally considered as being devoid of heat-producing qualities, and therefore worthless, can be made to produce great heat. With the new appliances, which change this garbage into gas, steam, and heat, an inconceivably great waste of money and energy can be avoided.

"The theory of the derivation of power in the form of gas and heat from garbage is not quite new, but the practical application of that theory is but a few weeks old. It is only six weeks since the works at Shoreditch, London, built under the supervision of scientists, for the conversion of garbage into gas, have been in operation, and they are a great success. From the garbage of that district, formerly carted away at great expense, enough energy is now being obtained to run the entire municipal plant of that part of the English capital; and so long as garbage can be had not an ounce of coal is needed.

"This lesson should have a weighty effect on other municipalities. Let them but remember that whatever garbage or refuse is collected has combustible qualities, and this combustion is the result of the discovery of a special furnace designed for that purpose. An ordinary fire will not extract gas from garbage. At a certain temperature which can only be obtained by the use of such a furnace the garbage will, by a process of evaporation, yield a considerable quantity of steam. Of course, as in the burning of coal, considerable slag is left over, the quantity being more or less, according to the quality of the garbage, but, then, this slag can be very well utilized in paving roadways."

Value of Garbage.

Lord Kelvin quoted some figures relative to this subject. He showed that while formerly Shorditch had expended a great deal of money to cart away the garbage, it was now deriving a good revenue from the plant. "The gas generated by combustion of this garbage," he continued, "comes off at a very high temperature, which does not require a coal fire, the refuse itself, or rather the cinders contained in the garbage, furnishing the basis of fuel. Oxygen also plays an important part in the production of this gas, and oxygen," he added, with a smile, "costs nothing—it's in the air.

"Very little labor is needed at the Shoreditch plant. A mechanical device dumps the refuse into the furnace, which is divided into a number of cells; and all that is needed is a man who does the slagging—that is, he takes out the remaining slag, pieces of glass and stone which, of course, will not burn."

Of the recent electrical demonstrations by Tesla, Lord Kelvin would say nothing. He pleaded insufficient acquaintance with their exact theories, and said he reading on those subjects had been meagre. He also declined to discuss the third-rail system now in operation on the New Britain and Hartford Road. He said he had come here to learn what the most ingenious people in the world were doing in the branch of electricity pertaining to motive power, and when he had seen all and examined all he would give his opinion. He will start for Niagara Falls this morning and will make an extensive inspection of the vast electrical plant there. From there he will go to Toronto, to attend the meeting of the British Association for the Advancement of Science, which opens Aug. 16.

Forty years ago Lord Kelvin was plain William Thomson, an electrical engineer. His electrical discoveries and the valuable assistance he gave in laying the Atlantic cables gained him knighthood. In 1892 he was elevated to the peerage.