In an urban setting, rooftop panels are the most practical, whereas rural properties generally have the benefit of adequate land for ground level installations. In either case, you would have the option of either photo-voltaic (PV) panels which generate electricity or thermal collectors(vacuum-tube or flat-panel) which heat water.
Think of it… perpetually free energy generated from a “clean” source – the sun! A pretty motivating idea for those of us paying the ever-rising cost of powering our homes from the electric company’s “grid”. Of course, there are costs associated with getting set up to harness the power of the sun, but once this one-time expense has been accounted for, this clean power resource is free!
Compelling reasons to collect natural energy from the sun:
- Reduce the cost of energy from the electric company’s “grid”
- Reduce harmful emissions from fossil fuel power plants
- Reduce the amount of natural gas burned to generate electricity
- Free energy, once equipment costs are paid off
Depending on availability of rooftop or ground-level space for mounting solar panels (both electric Photo-voltaic and/or thermal Vacuum-tube or the optional thermal Flat-panel), enough solar power could be generated to cover a portion or even ALL of your household needs.
SOLAR ELECTRIC POWER
How does it all work? When the sun’s rays come in contact with a properly sloped array of photovoltaic (PV) solar panels, the assembly of PV cells in each panel reacts, creating a flow of direct current (DC) electricity which is wired through an inverter, which then converts the DC to AC (alternating current). This AC power is then able to be utilized for household applications, once it is wired into a circuit breaker in the home’s main electrical panel. This electricity then travels up the buss bar in the main panel, and if anything in the home is drawing electricity, the solar power first goes to the home. If there is no draw in the home, this electricity will go out the main breaker, through the bi-directional meter and then join “grid” electricity in the main utility lines. This excess solar generated power will be used by others and paid for (to you) by the electric company.
Whether you choose to go completely “off-the- grid” with a battery back-up system (typical of remote locations) or to remain connected to a “grid” power supply (for secondary or emergency power), the solar electric energy you generate could be supplemented by other natural sources. Solar electric combined with solar thermal, geothermal or wind power (more about these later) could be harnessed together, acting as a hybrid system which could deliver the best of each resource. You would now be correct in concluding that there are very sustainable alternatives to “grid”-based power consumption, but the cost and viability of every alternate energy installation are subject to site-specific variables, such as location (urban, rural), available space, specific needs and of course, budget.
SOLAR THERMAL ENERGY
How does it all work? As with photo-voltaic (PV) solar panels which generate electricity, the sun’s rays first come in contact with a vacuum-tube (or a flat-plate) collector which is designed to generate heat. We will describe the vacuum-tube (as opposed to the flat-plate) collector, as it is more typically installed in our climate. This collector is made up of a series of inter-connected, evacuated tubes, each of which is a glass tube within another glass tube separated by a vacuum. The inner collection tube is made up of three different layers…one that absorbs radiant light (Photons), the next absorbs UV radiation and a third that has a special absorption coating that efficiently captures both radiant light and UV radiation. The heat generated collects in the inner tube and is focused on a copper pipe which contains a small volume of fluid that evaporates at 30 degrees Celcius. The steam produced moves to the top of the copper pipe where it condenses, transferring the heat into a manifold where a glycol solution absorbs the heat. This heated glycol is then pumped into a solar storage tank’s “closed-loop coil” where heat is transferred to domestic water for storage in a standard domestic hot water tank, for future use in showers, dishwashers, etc. The solar storage tank can also supply heat for fluid-based in-floor and baseboard heating systems. So, to summarize, the solar thermal energy collection system is all about heating water, while solar electric power is harnessed for electrical needs.
A Channel Custom Builders representative can help shed light on these somewhat complex issues. Contact Channel today to arrange for a complementary In-Home Consultation.