When Eat Local Month comes around, I like to think beyond our local farmers’ markets, Madison-based businesses and our overall goal of supporting our neighbors and creating a sustainable future. I like to think about what makes this possible and how small local systems contribute to the larger system that not only makes life on this planet possible, but also maintains the overall health of our biosphere. Last year I wrote about the importance of our local water system to our local sustainable food system and beyond. This time I want to talk about our very own star that makes everything possible on Earth. It provides all the energy, heat and light that we could ever possibly want and then some. Let’s talk about the power of our sun.
Making Life Possible
Our sun is about five billion years old and helped to form our planet into the thriving living system it is today. Without the gravitational pull of our sun, the Earth would never have existed and would still just be space dust and asteroids floating aimlessly in space. Even at a distance of 93 million miles, the sun’s gravitational pull brought the space debris together to form our Earth and hold it in orbit at precisely the right distance. That time would have been a violent one, with giant collisions releasing massive amounts of energy, which would eventually create Earth’s molten core (and surface as it cooled) and our moon.
With the creation of our wonderful planet, the sun’s influence on Earth was just beginning. As time wenton, the sun’s solar energy would be the major contributor to all energy driven forces on our planet’s surface. Solar energy helped to create our atmosphere, ocean currents, and our climate, which in turn allowed life to take hold and thrive on our planet.
Agriculture & Human Civilization
Towards the end of summer, you can’t help but think about the sun and all the amazing varieties of fresh fruits and vegetables it has helped to create. Just check out the Produce departments at either Willy Street Co-op and you will see a wide array of local purple produce tags highlighting all the incredible crops our local farms produce. It is this time of year that really helps me to appreciate the power of the sun as it gives us not only long, warm days, but plenty of opportunity to enjoy the local delicious bounty that the sun has provided.
Over a billion years ago, a bacteria that obtained the ability to absorb the sun’s energy was consumed by a single-celled organism that eventually evolved over time to become a prehistoric algae. Photosynthesis as we currently know it had been developed and Earth would never be the same. Now, nearly all life on our planet relies on the sun (and plants) for energy in the form of food and oxygen through the process of converting sunlight, carbon dioxide, and water into carbohydrates (sugars) and oxygen, or a process called photosynthesis.
We owe the sun for not only making life possible, but allowing human civilization to be created and thrive. The power of the sun allowed humans to grow crops, cultivate land and raise livestock. We could now grow the crops that we searched so long and hard for, harvest them and feed them to livestock we hunted so diligently for before they were domesticated.
From this point forward, humans learned more and more about the power of the sun. The sun (along with the moon and other stars) helped to develop crop rotation, calendars and seasons, cartography (map making), and guided the design and layout of our cities. Our connections to the sun are endless.
Utilizing Solar Energy
Besides the numerous natural processes driven by the sun, it is also responsible for nearly all forms of energy production that we currently use on Earth. All fossil fuels (oil, coal, natural gas) were at one time organic material created and sustained by the sun. Therefore, nearly all the potential energy trapped inside these fuels was created by solar energy. Most alternative energy can also be connected to the sun. Solar panels are clearly utilizing the sun’s radiation but so are wind turbines (wind is driven by heat/energy from the sun) and various forms of hydroelectric production (the sun makes the water cycle possible).
The sun radiates as much energy on Earth as people use across the globe in all forms in an entire year in just 15 minutes! However, direct solar collection produces less than one tenth of one percent of global energy demand. Something seems wrong here. We seem to be missing a vital opportunity to harness free, sustainable and renewable energy. Fossil fuels have been our major energy source for over 150 years and that has come at a considerable and potentially devastating cost. It is about time we look back to our ancestors and begin to utilize the power of our local star and it seems that is the direction we are going. Despite the minor drawbacks (energy storage and expense), solar energy use has surged at about 20% a year over the past 15 years, thanks to rapidly falling prices and gains in efficiency.
Willy East had a solar thermal unit installed about 10 years ago. This unit preheats all the water pumped into the hot water heater at the store. Although this might sound minimal, this system prevents approximately 3 tons of CO2 from entering the atmosphere every year.
In terms of distance, the sun is far from local. In terms of influence, the sun is at once a broad, unrestricted force and a hyperlocal powerhouse. The desire to eat local is directly linked to the seasonality and impact of the power of the sun. Without our longer warm summer days, we would have to ship in all of the incredible edibles that fill our Produce department as well as the other wonderful local products throughout our stores. And if done right (through preserving and storage) you can have these wonderfully nutritious treats throughout the year. So next time you bite into a Door County peach, Tipi carrot or Harmony Valley strawberry, remember to thank the sun!