Data study

South glass is the sunniest in 69 of 82 cities, north glass in 12.

Nearer the equator than about 37°, the sunny side switches for part of the summer: 15 days in Las Vegas, 191 in Nairobi. Montréal has the most on one face, 3,617 hours a year on south glass; at the equator every facing gets about the same 2,200.

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Why south, and why north

The sun crosses the sky on the side of the equator. North of the tropics that is the south; south of them, the north. A pane facing that way sees the sun all day, every day, and the further from the equator, the more it has over the pane facing away — at Melbourne (37.8°S) the north face gets 4.7 times the hours of the opposite one.

Below 37°, the sunny side switches for part of the summer

In early summer the sun rises far north of east and hangs in the north-east for hours before it crosses due east; it does the same in the north-west before it sets. At Las Vegas (36.2°N) those hours add up to more than the south face gets in between, so for 15 days around midsummer — June 13 to June 28 — the north-facing window is the sunnier one, in hours if not in warmth. Nearer the equator the spell lengthens: 191 days in Nairobi, where the sun passes overhead twice a year and stands on the north side of the sky in between. At the equator itself the two halves are equal, and east and west — half of every day each — match them almost exactly. Above about 37° the switch never happens: the south face keeps the sun every day of the year.

Hours are not warmth

Full-sun hours weigh each minute by how squarely the sun meets the glass and how much air it crosses. At high latitude the winter sun comes in low and head-on, so a south room there is warmest in the months with the fewest hours. That is the passive-solar rule of thumb, and here it is as a number for every city.

All 82 cities, north to south · 2026

Hours of direct sun a year. Tap a city for its numbers.

  1. Reykjavík64.2°NS 3,344 h

    Reykjavík, 64.2°N. South glass gets 3,344 hours of direct sun a year, worth 841 hours of full sun. North glass gets 1,084, east 2,215 and west 2,212. South glass has 3.6 hours of sun on the shortest day and 10.4 on the longest. Sun on a window in Reykjavík

  2. Helsinki60.2°NS 3,474 h

    Helsinki, 60.2°N. South glass gets 3,474 hours of direct sun a year, worth 894 hours of full sun. North glass gets 944, east 2,210 and west 2,208. South glass has 5.5 hours of sun on the shortest day and 10.1 on the longest. Sun on a window in Helsinki

  3. Oslo59.9°NS 3,480 h

    Oslo, 59.9°N. South glass gets 3,480 hours of direct sun a year, worth 897 hours of full sun. North glass gets 938, east 2,208 and west 2,210. South glass has 5.5 hours of sun on the shortest day and 10.1 on the longest. Sun on a window in Oslo

  4. Stockholm59.3°NS 3,493 h

    Stockholm, 59.3°N. South glass gets 3,493 hours of direct sun a year, worth 904 hours of full sun. North glass gets 924, east 2,209 and west 2,208. South glass has 5.7 hours of sun on the shortest day and 10.0 on the longest. Sun on a window in Stockholm

  5. Edinburgh56.0°NS 3,552 h

    Edinburgh, 56.0°N. South glass gets 3,552 hours of direct sun a year, worth 931 hours of full sun. North glass gets 860, east 2,206 and west 2,206. South glass has 6.7 hours of sun on the shortest day and 9.7 on the longest. Sun on a window in Edinburgh

  6. Moscow55.8°NS 3,555 h

    Moscow, 55.8°N. South glass gets 3,555 hours of direct sun a year, worth 932 hours of full sun. North glass gets 857, east 2,205 and west 2,207. South glass has 6.7 hours of sun on the shortest day and 9.7 on the longest. Sun on a window in Moscow

  7. Copenhagen55.7°NS 3,556 h

    Copenhagen, 55.7°N. South glass gets 3,556 hours of direct sun a year, worth 933 hours of full sun. North glass gets 856, east 2,205 and west 2,207. South glass has 6.7 hours of sun on the shortest day and 9.7 on the longest. Sun on a window in Copenhagen

  8. Hamburg53.5°NS 3,581 h

    Hamburg, 53.5°N. South glass gets 3,581 hours of direct sun a year, worth 941 hours of full sun. North glass gets 829, east 2,205 and west 2,204. South glass has 7.2 hours of sun on the shortest day and 9.5 on the longest. Sun on a window in Hamburg

  9. Dublin53.4°NS 3,582 h

    Dublin, 53.4°N. South glass gets 3,582 hours of direct sun a year, worth 942 hours of full sun. North glass gets 826, east 2,204 and west 2,204. South glass has 7.3 hours of sun on the shortest day and 9.5 on the longest. Sun on a window in Dublin

  10. Berlin52.5°NS 3,590 h

    Berlin, 52.5°N. South glass gets 3,590 hours of direct sun a year, worth 944 hours of full sun. North glass gets 818, east 2,204 and west 2,204. South glass has 7.4 hours of sun on the shortest day and 9.4 on the longest. Sun on a window in Berlin

  11. Amsterdam52.4°NS 3,591 h

    Amsterdam, 52.4°N. South glass gets 3,591 hours of direct sun a year, worth 944 hours of full sun. North glass gets 816, east 2,204 and west 2,203. South glass has 7.5 hours of sun on the shortest day and 9.4 on the longest. Sun on a window in Amsterdam

  12. Warsaw52.2°NS 3,592 h

    Warsaw, 52.2°N. South glass gets 3,592 hours of direct sun a year, worth 944 hours of full sun. North glass gets 816, east 2,204 and west 2,203. South glass has 7.5 hours of sun on the shortest day and 9.3 on the longest. Sun on a window in Warsaw

  13. London51.5°NS 3,598 h

    London, 51.5°N. South glass gets 3,598 hours of direct sun a year, worth 945 hours of full sun. North glass gets 808, east 2,204 and west 2,203. South glass has 7.6 hours of sun on the shortest day and 9.3 on the longest. Sun on a window in London

  14. Brussels50.9°NS 3,602 h

    Brussels, 50.9°N. South glass gets 3,602 hours of direct sun a year, worth 945 hours of full sun. North glass gets 804, east 2,203 and west 2,203. South glass has 7.7 hours of sun on the shortest day and 9.3 on the longest. Sun on a window in Brussels

  15. Prague50.1°NS 3,606 h

    Prague, 50.1°N. South glass gets 3,606 hours of direct sun a year, worth 944 hours of full sun. North glass gets 800, east 2,203 and west 2,203. South glass has 7.8 hours of sun on the shortest day and 9.1 on the longest. Sun on a window in Prague

  16. Vancouver49.3°NS 3,610 h

    Vancouver, 49.3°N. South glass gets 3,610 hours of direct sun a year, worth 943 hours of full sun. North glass gets 794, east 2,203 and west 2,201. South glass has 8.0 hours of sun on the shortest day and 9.1 on the longest. Sun on a window in Vancouver

  17. Paris48.9°NS 3,611 h

    Paris, 48.9°N. South glass gets 3,611 hours of direct sun a year, worth 942 hours of full sun. North glass gets 792, east 2,202 and west 2,201. South glass has 8.1 hours of sun on the shortest day and 9.0 on the longest. Sun on a window in Paris

  18. Vienna48.2°NS 3,614 h

    Vienna, 48.2°N. South glass gets 3,614 hours of direct sun a year, worth 940 hours of full sun. North glass gets 790, east 2,202 and west 2,202. South glass has 8.1 hours of sun on the shortest day and 9.0 on the longest. Sun on a window in Vienna

  19. Munich48.1°NS 3,613 h

    Munich, 48.1°N. South glass gets 3,613 hours of direct sun a year, worth 940 hours of full sun. North glass gets 789, east 2,201 and west 2,202. South glass has 8.2 hours of sun on the shortest day and 9.0 on the longest. Sun on a window in Munich

  20. Seattle47.6°NS 3,614 h

    Seattle, 47.6°N. South glass gets 3,614 hours of direct sun a year, worth 938 hours of full sun. North glass gets 788, east 2,201 and west 2,202. South glass has 8.2 hours of sun on the shortest day and 8.9 on the longest. Sun on a window in Seattle

  21. Zürich47.4°NS 3,616 h

    Zürich, 47.4°N. South glass gets 3,616 hours of direct sun a year, worth 937 hours of full sun. North glass gets 787, east 2,201 and west 2,202. South glass has 8.2 hours of sun on the shortest day and 8.9 on the longest. Sun on a window in Zürich

  22. Portland45.5°NS 3,616 h

    Portland, 45.5°N. South glass gets 3,616 hours of direct sun a year, worth 927 hours of full sun. North glass gets 785, east 2,200 and west 2,201. South glass has 8.5 hours of sun on the shortest day and 8.6 on the longest. Sun on a window in Portland

  23. Montréal45.5°NS 3,617 h

    Montréal, 45.5°N. South glass gets 3,617 hours of direct sun a year, worth 927 hours of full sun. North glass gets 785, east 2,201 and west 2,201. South glass has 8.5 hours of sun on the shortest day and 8.6 on the longest. Sun on a window in Montréal

  24. Milan45.5°NS 3,616 h

    Milan, 45.5°N. South glass gets 3,616 hours of direct sun a year, worth 927 hours of full sun. North glass gets 784, east 2,200 and west 2,200. South glass has 8.5 hours of sun on the shortest day and 8.7 on the longest. Sun on a window in Milan

  25. Venice45.4°NS 3,617 h

    Venice, 45.4°N. South glass gets 3,617 hours of direct sun a year, worth 927 hours of full sun. North glass gets 785, east 2,201 and west 2,200. South glass has 8.5 hours of sun on the shortest day and 8.6 on the longest. Sun on a window in Venice

  26. Minneapolis45.0°NS 3,616 h

    Minneapolis, 45.0°N. South glass gets 3,616 hours of direct sun a year, worth 924 hours of full sun. North glass gets 784, east 2,199 and west 2,201. South glass has 8.6 hours of sun on the shortest day and 8.6 on the longest. Sun on a window in Minneapolis

  27. Nice43.7°NS 3,615 h

    Nice, 43.7°N. South glass gets 3,615 hours of direct sun a year, worth 915 hours of full sun. North glass gets 785, east 2,200 and west 2,200. South glass has 8.7 hours of sun on the shortest day and 8.4 on the longest. Sun on a window in Nice

  28. Toronto43.6°NS 3,614 h

    Toronto, 43.6°N. South glass gets 3,614 hours of direct sun a year, worth 915 hours of full sun. North glass gets 785, east 2,199 and west 2,201. South glass has 8.7 hours of sun on the shortest day and 8.4 on the longest. Sun on a window in Toronto

  29. Boston42.4°NS 3,611 h

    Boston, 42.4°N. South glass gets 3,611 hours of direct sun a year, worth 904 hours of full sun. North glass gets 787, east 2,199 and west 2,199. South glass has 8.9 hours of sun on the shortest day and 8.3 on the longest. Sun on a window in Boston

  30. Rome41.9°NS 3,609 h

    Rome, 41.9°N. South glass gets 3,609 hours of direct sun a year, worth 900 hours of full sun. North glass gets 789, east 2,199 and west 2,199. South glass has 9.0 hours of sun on the shortest day and 8.2 on the longest. Sun on a window in Rome

  31. Chicago41.9°NS 3,609 h

    Chicago, 41.9°N. South glass gets 3,609 hours of direct sun a year, worth 900 hours of full sun. North glass gets 789, east 2,199 and west 2,199. South glass has 8.9 hours of sun on the shortest day and 8.1 on the longest. Sun on a window in Chicago

  32. Barcelona41.4°NS 3,606 h

    Barcelona, 41.4°N. South glass gets 3,606 hours of direct sun a year, worth 895 hours of full sun. North glass gets 792, east 2,200 and west 2,199. South glass has 9.0 hours of sun on the shortest day and 8.1 on the longest. Sun on a window in Barcelona

  33. Porto41.1°NS 3,606 h

    Porto, 41.1°N. South glass gets 3,606 hours of direct sun a year, worth 893 hours of full sun. North glass gets 792, east 2,199 and west 2,199. South glass has 9.0 hours of sun on the shortest day and 8.1 on the longest. Sun on a window in Porto

  34. Salt Lake City40.8°NS 3,603 h

    Salt Lake City, 40.8°N. South glass gets 3,603 hours of direct sun a year, worth 889 hours of full sun. North glass gets 794, east 2,199 and west 2,198. South glass has 9.1 hours of sun on the shortest day and 8.0 on the longest. Sun on a window in Salt Lake City

  35. New York40.7°NS 3,603 h

    New York, 40.7°N. South glass gets 3,603 hours of direct sun a year, worth 889 hours of full sun. North glass gets 794, east 2,199 and west 2,198. South glass has 9.1 hours of sun on the shortest day and 8.0 on the longest. Sun on a window in New York

  36. Madrid40.4°NS 3,602 h

    Madrid, 40.4°N. South glass gets 3,602 hours of direct sun a year, worth 886 hours of full sun. North glass gets 796, east 2,199 and west 2,198. South glass has 9.1 hours of sun on the shortest day and 7.9 on the longest. Sun on a window in Madrid

  37. Philadelphia40.0°NS 3,598 h

    Philadelphia, 40.0°N. South glass gets 3,598 hours of direct sun a year, worth 881 hours of full sun. North glass gets 798, east 2,199 and west 2,198. South glass has 9.2 hours of sun on the shortest day and 7.9 on the longest. Sun on a window in Philadelphia

  38. Beijing39.9°NS 3,598 h

    Beijing, 39.9°N. South glass gets 3,598 hours of direct sun a year, worth 880 hours of full sun. North glass gets 799, east 2,199 and west 2,199. South glass has 9.1 hours of sun on the shortest day and 7.8 on the longest. Sun on a window in Beijing

  39. Denver39.7°NS 3,597 h

    Denver, 39.7°N. South glass gets 3,597 hours of direct sun a year, worth 878 hours of full sun. North glass gets 799, east 2,199 and west 2,197. South glass has 9.2 hours of sun on the shortest day and 7.9 on the longest. Sun on a window in Denver

  40. Washington, DC38.9°NS 3,591 h

    Washington, DC, 38.9°N. South glass gets 3,591 hours of direct sun a year, worth 869 hours of full sun. North glass gets 806, east 2,199 and west 2,198. South glass has 9.3 hours of sun on the shortest day and 7.7 on the longest. Sun on a window in Washington, DC

  41. Lisbon38.7°NS 3,589 h

    Lisbon, 38.7°N. South glass gets 3,589 hours of direct sun a year, worth 867 hours of full sun. North glass gets 807, east 2,199 and west 2,197. South glass has 9.3 hours of sun on the shortest day and 7.6 on the longest. Sun on a window in Lisbon

  42. Athens38.0°NS 3,583 h

    Athens, 38.0°N. South glass gets 3,583 hours of direct sun a year, worth 858 hours of full sun. North glass gets 813, east 2,198 and west 2,199. South glass has 9.4 hours of sun on the shortest day and 7.5 on the longest. Sun on a window in Athens

  43. San Francisco37.8°NS 3,580 h

    San Francisco, 37.8°N. South glass gets 3,580 hours of direct sun a year, worth 856 hours of full sun. North glass gets 815, east 2,196 and west 2,199. South glass has 9.4 hours of sun on the shortest day and 7.5 on the longest. Sun on a window in San Francisco

  44. Seoul37.6°NS 3,579 h

    Seoul, 37.6°N. South glass gets 3,579 hours of direct sun a year, worth 853 hours of full sun. North glass gets 817, east 2,199 and west 2,198. South glass has 9.5 hours of sun on the shortest day and 7.5 on the longest. Sun on a window in Seoul

  45. Las Vegas36.2°NS 3,564 h

    Las Vegas, 36.2°N. South glass gets 3,564 hours of direct sun a year, worth 835 hours of full sun. North glass gets 832, east 2,198 and west 2,197. South glass has 9.5 hours of sun on the shortest day and 7.2 on the longest. North glass is the sunnier side from June 13 to June 28. Sun on a window in Las Vegas

  46. Nashville36.2°NS 3,563 h

    Nashville, 36.2°N. South glass gets 3,563 hours of direct sun a year, worth 835 hours of full sun. North glass gets 831, east 2,198 and west 2,197. South glass has 9.5 hours of sun on the shortest day and 7.1 on the longest. North glass is the sunnier side from June 12 to July 1. Sun on a window in Nashville

  47. Tokyo35.7°NS 3,558 h

    Tokyo, 35.7°N. South glass gets 3,558 hours of direct sun a year, worth 829 hours of full sun. North glass gets 837, east 2,197 and west 2,198. South glass has 9.6 hours of sun on the shortest day and 7.1 on the longest. North glass is the sunnier side from June 10 to July 5. Sun on a window in Tokyo

  48. Kyoto35.0°NS 3,548 h

    Kyoto, 35.0°N. South glass gets 3,548 hours of direct sun a year, worth 820 hours of full sun. North glass gets 846, east 2,197 and west 2,198. South glass has 9.7 hours of sun on the shortest day and 6.9 on the longest. North glass is the sunnier side from June 7 to July 7. Sun on a window in Kyoto

  49. Osaka34.7°NS 3,544 h

    Osaka, 34.7°N. South glass gets 3,544 hours of direct sun a year, worth 815 hours of full sun. North glass gets 849, east 2,197 and west 2,197. South glass has 9.7 hours of sun on the shortest day and 6.9 on the longest. North glass is the sunnier side from June 6 to July 8. Sun on a window in Osaka

  50. Los Angeles34.0°NS 3,534 h

    Los Angeles, 34.0°N. South glass gets 3,534 hours of direct sun a year, worth 806 hours of full sun. North glass gets 859, east 2,197 and west 2,196. South glass has 9.7 hours of sun on the shortest day and 6.7 on the longest. North glass is the sunnier side from June 2 to July 12. Sun on a window in Los Angeles

  51. Atlanta33.8°NS 3,530 h

    Atlanta, 33.8°N. South glass gets 3,530 hours of direct sun a year, worth 802 hours of full sun. North glass gets 864, east 2,197 and west 2,198. South glass has 9.8 hours of sun on the shortest day and 6.6 on the longest. North glass is the sunnier side from June 1 to July 12. Sun on a window in Atlanta

  52. Phoenix33.5°NS 3,524 h

    Phoenix, 33.5°N. South glass gets 3,524 hours of direct sun a year, worth 797 hours of full sun. North glass gets 870, east 2,197 and west 2,196. South glass has 9.8 hours of sun on the shortest day and 6.5 on the longest. North glass is the sunnier side from May 31 to July 12. Sun on a window in Phoenix

  53. Dallas32.8°NS 3,513 h

    Dallas, 32.8°N. South glass gets 3,513 hours of direct sun a year, worth 788 hours of full sun. North glass gets 880, east 2,197 and west 2,196. South glass has 9.9 hours of sun on the shortest day and 6.3 on the longest. North glass is the sunnier side from May 29 to July 15. Sun on a window in Dallas

  54. San Diego32.7°NS 3,512 h

    San Diego, 32.7°N. South glass gets 3,512 hours of direct sun a year, worth 787 hours of full sun. North glass gets 881, east 2,197 and west 2,196. South glass has 9.9 hours of sun on the shortest day and 6.3 on the longest. North glass is the sunnier side from May 28 to July 15. Sun on a window in San Diego

  55. Tel Aviv32.1°NS 3,499 h

    Tel Aviv, 32.1°N. South glass gets 3,499 hours of direct sun a year, worth 777 hours of full sun. North glass gets 894, east 2,196 and west 2,196. South glass has 9.9 hours of sun on the shortest day and 6.1 on the longest. North glass is the sunnier side from May 27 to July 18. Sun on a window in Tel Aviv

  56. Shanghai31.2°NS 3,481 h

    Shanghai, 31.2°N. South glass gets 3,481 hours of direct sun a year, worth 764 hours of full sun. North glass gets 911, east 2,196 and west 2,196. South glass has 9.9 hours of sun on the shortest day and 5.9 on the longest. North glass is the sunnier side from May 24 to July 21. Sun on a window in Shanghai

  57. Austin30.3°NS 3,459 h

    Austin, 30.3°N. South glass gets 3,459 hours of direct sun a year, worth 748 hours of full sun. North glass gets 933, east 2,196 and west 2,196. South glass has 10.1 hours of sun on the shortest day and 5.6 on the longest. North glass is the sunnier side from May 20 to July 23. Sun on a window in Austin

  58. New Orleans29.9°NS 3,450 h

    New Orleans, 29.9°N. South glass gets 3,450 hours of direct sun a year, worth 743 hours of full sun. North glass gets 942, east 2,196 and west 2,196. South glass has 10.1 hours of sun on the shortest day and 5.5 on the longest. North glass is the sunnier side from May 20 to July 24. Sun on a window in New Orleans

  59. Houston29.8°NS 3,445 h

    Houston, 29.8°N. South glass gets 3,445 hours of direct sun a year, worth 740 hours of full sun. North glass gets 946, east 2,194 and west 2,197. South glass has 10.1 hours of sun on the shortest day and 5.4 on the longest. North glass is the sunnier side from May 20 to July 24. Sun on a window in Houston

  60. Delhi28.6°NS 3,412 h

    Delhi, 28.6°N. South glass gets 3,412 hours of direct sun a year, worth 721 hours of full sun. North glass gets 979, east 2,196 and west 2,196. South glass has 10.2 hours of sun on the shortest day and 5.0 on the longest. North glass is the sunnier side from May 17 to July 28. Sun on a window in Delhi

  61. Miami25.8°NS 3,301 h

    Miami, 25.8°N. South glass gets 3,301 hours of direct sun a year, worth 673 hours of full sun. North glass gets 1,088, east 2,195 and west 2,195. South glass has 10.4 hours of sun on the shortest day and 3.5 on the longest. North glass is the sunnier side from May 10 to August 3. Sun on a window in Miami

  62. Taipei25.0°NS 3,262 h

    Taipei, 25.0°N. South glass gets 3,262 hours of direct sun a year, worth 661 hours of full sun. North glass gets 1,127, east 2,194 and west 2,195. South glass has 10.5 hours of sun on the shortest day and 2.9 on the longest. North glass is the sunnier side from May 9 to August 5. Sun on a window in Taipei

  63. Hong Kong22.3°NS 3,035 h

    Hong Kong, 22.3°N. South glass gets 3,035 hours of direct sun a year, worth 616 hours of full sun. North glass gets 1,353, east 2,194 and west 2,193. South glass has 10.7 hours of sun on the shortest day and 0.0 on the longest. North glass is the sunnier side from May 2 to August 11. Sun on a window in Hong Kong

  64. Honolulu21.3°NS 2,970 h

    Honolulu, 21.3°N. South glass gets 2,970 hours of direct sun a year, worth 600 hours of full sun. North glass gets 1,418, east 2,194 and west 2,194. South glass has 10.7 hours of sun on the shortest day and 0.0 on the longest. North glass is the sunnier side from April 29 to August 13. Sun on a window in Honolulu

  65. Mexico City19.4°NS 2,866 h

    Mexico City, 19.4°N. South glass gets 2,866 hours of direct sun a year, worth 572 hours of full sun. North glass gets 1,520, east 2,194 and west 2,193. South glass has 10.8 hours of sun on the shortest day and 0.0 on the longest. North glass is the sunnier side from April 26 to August 17. Sun on a window in Mexico City

  66. Mumbai19.1°NS 2,849 h

    Mumbai, 19.1°N. South glass gets 2,849 hours of direct sun a year, worth 566 hours of full sun. North glass gets 1,538, east 2,193 and west 2,193. South glass has 10.9 hours of sun on the shortest day and 0.0 on the longest. North glass is the sunnier side from April 26 to August 18. Sun on a window in Mumbai

  67. Bangkok13.8°NS 2,619 h

    Bangkok, 13.8°N. South glass gets 2,619 hours of direct sun a year, worth 488 hours of full sun. North glass gets 1,765, east 2,192 and west 2,193. South glass has 11.1 hours of sun on the shortest day and 0.0 on the longest. North glass is the sunnier side from April 15 to August 29. Sun on a window in Bangkok

  68. Bengaluru13.0°NS 2,588 h

    Bengaluru, 13.0°N. South glass gets 2,588 hours of direct sun a year, worth 476 hours of full sun. North glass gets 1,795, east 2,192 and west 2,191. South glass has 11.2 hours of sun on the shortest day and 0.0 on the longest. North glass is the sunnier side from April 13 to August 30. Sun on a window in Bengaluru

  69. Bogotá4.7°NS 2,297 h

    Bogotá, 4.7°N. South glass gets 2,297 hours of direct sun a year, worth 361 hours of full sun. North glass gets 2,084, east 2,191 and west 2,190. South glass has 11.7 hours of sun on the shortest day and 0.0 on the longest. North glass is the sunnier side from March 29 to September 14. Sun on a window in Bogotá

  70. Singapore1.4°NSE 2,213 h

    Singapore, 1.4°N. South-east glass gets 2,213 hours of direct sun a year, worth 504 hours of full sun. North glass gets 2,194, east 2,190, south 2,187 and west 2,190. South-east glass has 7.7 hours of sun on the shortest day and 4.4 on the longest. North glass is the sunnier side from March 23 to September 21. All four sides are within 0% of each other. Sun on a window in Singapore

  71. Nairobi1.3°SN 2,278 h

    Nairobi, 1.3°S. North glass gets 2,278 hours of direct sun a year, worth 332 hours of full sun. East glass gets 2,190, south 2,102 and west 2,190. North glass has 11.9 hours of sun on the shortest day and 0.0 on the longest. South glass is the sunnier side from September 25 to March 18. Sun on a window in Nairobi

  72. Lima12.1°SN 2,637 h

    Lima, 12.1°S. North glass gets 2,637 hours of direct sun a year, worth 484 hours of full sun. East glass gets 2,188, south 1,739 and west 2,189. North glass has 11.3 hours of sun on the shortest day and 0.0 on the longest. South glass is the sunnier side from October 15 to February 27. Sun on a window in Lima

  73. Rio de Janeiro22.9°SN 3,135 h

    Rio de Janeiro, 22.9°S. North glass gets 3,135 hours of direct sun a year, worth 648 hours of full sun. East glass gets 2,186, south 1,236 and west 2,185. North glass has 10.6 hours of sun on the shortest day and 0.0 on the longest. South glass is the sunnier side from November 5 to February 6. Sun on a window in Rio de Janeiro

  74. São Paulo23.6°SN 3,199 h

    São Paulo, 23.6°S. North glass gets 3,199 hours of direct sun a year, worth 658 hours of full sun. East glass gets 2,186, south 1,171 and west 2,185. North glass has 10.6 hours of sun on the shortest day and 0.8 on the longest. South glass is the sunnier side from November 7 to February 5. Sun on a window in São Paulo

  75. Brisbane27.5°SN 3,407 h

    Brisbane, 27.5°S. North glass gets 3,407 hours of direct sun a year, worth 723 hours of full sun. East glass gets 2,185, south 962 and west 2,184. North glass has 10.3 hours of sun on the shortest day and 4.5 on the longest. South glass is the sunnier side from November 16 to January 28. Sun on a window in Brisbane

  76. Perth31.9°SN 3,518 h

    Perth, 31.9°S. North glass gets 3,518 hours of direct sun a year, worth 794 hours of full sun. East glass gets 2,184, south 849 and west 2,183. North glass has 9.9 hours of sun on the shortest day and 6.1 on the longest. South glass is the sunnier side from November 27 to January 17. Sun on a window in Perth

  77. Santiago33.5°SN 3,544 h

    Santiago, 33.5°S. North glass gets 3,544 hours of direct sun a year, worth 816 hours of full sun. East glass gets 2,184, south 823 and west 2,183. North glass has 9.8 hours of sun on the shortest day and 6.5 on the longest. South glass is the sunnier side from December 1 to January 11. Sun on a window in Santiago

  78. Sydney33.9°SN 3,550 h

    Sydney, 33.9°S. North glass gets 3,550 hours of direct sun a year, worth 821 hours of full sun. East glass gets 2,183, south 817 and west 2,184. North glass has 9.7 hours of sun on the shortest day and 6.7 on the longest. South glass is the sunnier side from December 3 to January 11. Sun on a window in Sydney

  79. Cape Town33.9°SN 3,550 h

    Cape Town, 33.9°S. North glass gets 3,550 hours of direct sun a year, worth 822 hours of full sun. East glass gets 2,183, south 816 and west 2,184. North glass has 9.8 hours of sun on the shortest day and 6.6 on the longest. South glass is the sunnier side from December 3 to January 11. Sun on a window in Cape Town

  80. Buenos Aires34.6°SN 3,559 h

    Buenos Aires, 34.6°S. North glass gets 3,559 hours of direct sun a year, worth 831 hours of full sun. East glass gets 2,182, south 807 and west 2,184. North glass has 9.7 hours of sun on the shortest day and 6.9 on the longest. South glass is the sunnier side from December 6 to January 6. Sun on a window in Buenos Aires

  81. Auckland36.9°SN 3,585 h

    Auckland, 36.9°S. North glass gets 3,585 hours of direct sun a year, worth 860 hours of full sun. East glass gets 2,182, south 781 and west 2,183. North glass has 9.5 hours of sun on the shortest day and 7.3 on the longest. Sun on a window in Auckland

  82. Melbourne37.8°SN 3,592 h

    Melbourne, 37.8°S. North glass gets 3,592 hours of direct sun a year, worth 871 hours of full sun. East glass gets 2,182, south 772 and west 2,182. North glass has 9.3 hours of sun on the shortest day and 7.5 on the longest. Sun on a window in Melbourne

Method

For every city in Sol's fleet, the sun's position (a compact NOAA-style algorithm, good to about 0.1°) is sampled every four minutes on every day of 2026. A vertical pane faces one of the eight compass points. A minute counts as direct sun when the sun is above an open, flat horizon and within 90° of the facing. Full-sun hours weigh each minute by the cosine of incidence and a clear-sky beam (Kasten–Young air mass, Meinel attenuation). No clouds, no obstructions, no reflections: the numbers are what the geometry allows, an upper bound that every real window sits below. "Sunniest" is the facing with the most hours; where the four cardinals lie within 5% of each other the city is marked even. Coordinates are the city centres in the fleet. The code that produced every number is on the page: window-tools.js.

Computed 2026-10-30 03:02 UTC for 2026 · clear sky, open horizon · the geometry's upper bound.

Cite this.

Sol (2026). The sunniest facing in 82 cities: hours of direct sun a year by the way a window faces. https://solocene.com/studies/sunniest-facing

Free to quote and reuse with a link (CC BY 4.0). The CSV and JSON carry every number on this page.

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