It is impossible to overstate the importance of solar energy to human life – it’s essential to everything we do.
Without the Sun, crops wouldn’t grow – in fact, the planet would be entirely devoid of life.
Because the uses of solar energy are so broad, we’re going to have to narrow things down. You won’t find “sustaining all life on the planet” on this list because we’re going to talk, instead, about the most common ways solar energy is used to reduce greenhouse gas emissions.
We’re going to focus on the two ways solar energy is most used to reduce carbon emissions: for heating, and for the production of electricity. We’re going to look at two broad ways it can be used for heating, and three wide-ranging applications for solar electricity production.
Let’s get started.
Passive heating for buildings
For most of human history, solar heating was the primary source of heating for most buildings during the day. Culturally, we shifted away from passive heating principles because of access to fossil fuels, which were readily available.
Now that we more fully appreciate the gravity of using fossil fuels to heat our buildings, many designers have shifted back to passive heating principles. The core of passive solar heating is simple: create structures that absorb heat during the day, then release it at night.
Masonry is commonly used for passive heating. Brick, stone, tile, and even concrete absorb heat from the Sun more quickly than they emit it. You can think of this masonry – sometimes called thermal mass – as something like a solar heat battery. They charge up by absorbing heat during the day, then they release that same heat at night to keep the building warm during the cooler hours.
There are a variety of ways thermal masses can be employed in buildings to absorb and release more (or less) heat depending on the climate, the building’s occupancy, and whether it’s a new build or a renovation. Direct and indirect gain are both useful options.
Passive heating is underused right now, but that may be because renovating a home is more difficult than, say, installing solar panels. We expect to see more passive solar heating in the near future. This will be coupled with better insulation, which can reduce your AC power consumption as well as your furnace power consumption.
Solar water heating
Solar water heaters are growing in popularity – China is dominating the rest of the world in the solar water heating race, and we expect other countries will try to catch up. We are, after all, always looking for new and efficient heating solutions. There are several different solar water heater designs – some more efficient than others.
There are two general categories of solar water heaters: active systems, which use a pump, and passive systems, which rely on convection and fluid dynamics to move water. Active systems tend to be more effective (and more expensive) than passive systems.
There are also both direct and indirect solar water heating systems. The indirect systems are most commonly used in regions that fall below freezing temperatures. They use fluids like antifreeze, then use a heat exchanger, similar to what you’d find in a heat pump, to transfer heat from the antifreeze outside to the water inside.
Direct systems, on the other hand, heat water directly.
You can also use solar water heating to heat your pool, though the principles used are somewhat different. In all of these cases, however, the main ingredient is solar energy. Solar collectors are specially designed to absorb as much heat energy as possible from the Sun and heat the water.
Solar power for buildings
When you think of common uses for solar energy, this is probably the first one that comes to mind. And there’s a good reason for that – solar power is now the least expensive form of electricity that has ever existed.
No wonder it’s becoming so popular.
Expect to see more solar panels on homes near you – and on larger buildings, too. We’re at the point that solar panels can do more than just power off-grid homes. You can live in a luxury home with a smart fridge, a home theatre, and an at-home EV charging station – all on the power of solar.
Now, solar power isn’t magic – you still need to have a sizable array if you want to power a home like we just described, and you’ll still need a source of power in the winter. Fortunately, many utilities offer net metering – you sell them your excess energy each summer, and they give you credits you can use in the winter.
We expect that, despite solar’s limitations, more utilities are going to build massive solar farms – solar power is just that efficient.
Solar-powered lighting
Lighting is a particularly good use of solar power. During the day, solar panels can absorb energy, then store it in solar batteries. Outdoor lights, of course, only need to be activated at night. That means the solar energy they gain during the day is used up every night, and the cycle repeats the next day.
Lighting doesn’t take a lot of power, so solar lighting gets around one of the biggest issues with solar power – batteries can’t store very much energy. With their low energy consumption and 24-hour cycles, the limitations of batteries are no problem for solar lights.
There are all types of solar lighting arrays available – many lights have the solar panels installed directly onto them, while some arrays draw their energy from a central solar system.
They’re becoming incredibly popular for lighting parking lots, paths, billboards, and other outdoor fixtures that businesses want to keep lit.
Miniature solar
Solar panels can be made very small – some of you may have even had solar-powered calculators in your youth. That’s a good thing, because it means we can use solar almost anywhere.
One of the most popular forms of miniature solar is the portable solar charger. They can be used to charge your phone, or anything else that charges via USB. You can also find solar-powered flashlights, solar-powered Bluetooth speakers, and a whole lot more. As solar becomes more efficient, expect more portable technologies to get some of their power from the Sun.
Conclusion
As you can see, there are a lot of pretty incredible uses for solar energy. The Sun may be our most powerful tool in the fight against climate change. Want to take part? Take stock of how you use energy. Then, try to determine what solar upgrades are within your budget, and implement them. Remember, solar energy will save you money over time, and there are often grants available for upgrading to solar.
The future looks bright.
