Solar Power

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With solar power, you can convert renewable energy into heat or electricity to power your home. This offers an environmentally friendly solution for your gas and electricity needs, while significantly reducing your energy bill. Now is the best time to consider solar, as the State of California and the US Energy department currently offer rebates and federal tax credits as incentives for the transition. By taking advantage of these incentives, you can reduce the cost of your investment now, so that you will save on the cost of your energy later!

Solar energy is harnessed for your home primarily using two methods: 1) solar electric and 2) solar thermal, and each method typically serves a different function. Let us briefly explore how they work.

Section Contents
- Solar Electric
– Micro Inverters
- Solar Thermal

Solar Electric

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Solar electric is a method which harnesses the sun’s energy to generate electricity. A mountable body, known as a solar panel, houses arrays of photovoltaic cells and a semiconducting surface to capture sunlight. For reference, the adjacent photo depicts an array of such solar panels mounted to a client’s roof at one of our job sites.

Sunlight consists of particles known as photons, which strike the surface of a solar panel, where a semiconducting material (i.e. monocrystalline or silicon) absorbs them. The photons displace electrons from the atoms in the cells, which allow them to freely flow and produce usable electricity.

Solar electric really only requires sunlight and a surface in which to mount the panels. As a result, it works as a versatile method for harnessing renewable energy for many environments, including your own home.

Microinverters

A solar photovoltaic microinverter is a device used to convert direct current to alternating current from a single solar module. This enables the solar modules to be connected in parallel by converting DC power to AC power on a per-module basis. This carries the benefit of minimizing energy production loss to a single module should an individual microinverter fail; whereas, energy production from the entire array would be lost in the failure of a central inverter until the unit is replaced.

A grid-tie photovoltaic microinverter regulates the power supplies to ensure compliancy with the grid power. In locations where energy buyback agreements are in place, which includes all of the areas serviced by Green Air, this allows installations to sell surplus power back to the utility company.

Microinverters also serve the purpose of optimizing maximum power point tracking (MPPT), which is an algorithm designed to extract the greatest power available from the solar array. Due to small manufacturing deviations among individual modules, optimal MPPT may vary among each constituent of the array. While this would certainly present an issue for a central inverter, which can only manage MPPT at the level of the entire array, the installation of microinverters allows for optimal system effiency by managing MPPT at the module level.

Solar Thermal

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Solar thermal collectors make use of the sun to store energy through the use of a thermal mass, such as water, stone, brick, etc. The energy stored in the thermal mass may then be used to heat other bodies, such as water in a swimming pool or to provide space heating. On a larger scale, solar thermal may also generate electricity by directing and concentrating sunlight using lenses or mirrors.

With many available surfaces to act as a thermal mass, solar thermal represents a viable and economic method to facilitate the process of space or hydronic heating for your home.