Solar Panels for Your Home - Frequently Asked Questions

Most of the homes I’ve built over the last 17 years have included solar panels for producing energy. When consulting with clients about the merits of installing solar, I've fielded many questions. Below are a handful of topics that come up fairly frequently.

1.)     First, a basic one - How do solar panels work?

Solar panels (photovoltaic panels) convert sunlight into electricity through the photovoltaic effect. They are composed of many individual solar cells made from semiconductor materials (silicon – the same thing computer chips are made from). When sunlight hits these cells, it generates an electric field across the layers, creating a flow of electricity. This direct current (DC) is then converted to alternating current (AC) by an inverter, the type of electricity used in homes.

2.)     What are the benefits of installing solar panels?

First, they are a good investment.  Most homeowners can expect a return on their investment of between 5-10 years.  Depending on the electric utility, there may be additional incentives that shorten the ROI.  Additionally, some utilities have special billing practices (for example: time-of-use billing) that make solar an even more favorable investment.  A solar array will also increase the home's value if the homeowner decides to sell.

Additionally, if the solar array is installed when the home is being constructed, the cost of the system can be added to the mortgage. The savings achieved by reducing the home's energy costs will be larger than the additional cost of the home’s mortgage payments, immediately making it cash flow positive.

For the environmentally minded, they contribute to reducing your carbon footprint by decreasing reliance on fossil fuels.

3.)     What is the cost of installing solar panels?

The cost of solar panel installation is primarily driven by the size of the system.   In today’s market, it’s common to see install prices around $3~3.50/watt.  So, a 10-kilowatt system (which would be a typical size) would run between $30~35K.  The federal tax credits will cover 30% of this cost, making the out-of-pocket around $21~24.5K.  There may be other local government and utility incentives that will decrease this cost further.

4.)     How long do solar panels last?

Solar panels are designed to be durable and typically come with a warranty of 20 to 25 years. Most panels will continue to produce electricity far beyond this period, although their efficiency may gradually decrease over time.  There are panels that were installed in the 1980’s that are still producing power today, and that’s from technology many generations ago.

5.)     Do solar panels work on cloudy days (or at night – LOL)?

Solar panels do produce electricity on cloudy days, although their output is reduced compared to sunny conditions. They work on the principle of capturing available sunlight, so even diffused light can generate power (although, sadly not light reflected from the moon).

6.)     What maintenance do solar panels require?

Solar panels require minimal maintenance. It is generally recommended to keep them clean and free from debris such as leaves or bird droppings, which can block sunlight and reduce efficiency.  In reality, most homeowners let the rain take care of any cleaning, and this is generally sufficient.

7.)     How much energy will solar panels generate for my home?

The amount of energy solar panels generate depends on several factors, including the size of the system, the efficiency of the panels, and the amount of sunlight it receives (orientation of the panels, shading, etc.). A typical residential solar system can cover a significant portion of a household’s electricity needs, but the exact percentage varies.  It is possible to offset your energy 100%.

8.)     If we have a power outage, will the panels keep electricity flowing to my home?

Unfortunately, the answer is “no.” The systems are designed to shut down in the event of a power outage. This is for the safety of the technicians working on the power lines. We don’t want to feed electricity back into the power lines and create a dangerous situation. 

The workaround is to install batteries. The batteries come with switching gear that allows the system to isolate the home electrical system from that of the power grid. This allows the solar panels to continue producing power and charging the batteries, which then provide power to the home.

9.)     Should I consider batteries for my home?

This is a big topic, and I will cover it in a future white paper… stay tuned…