In order to have this discussion, it is necessary to look at electrical energy consumption patterns. Our energy sources have to match the timing of our consumption. The graphs below show the typical daily electrical energy consumption patterns for residential and commercial consumers.
During the first 10 years in service, the chance of failure within a PV system is approximately 10%. Inverters and other electronic devices account for 85% of all those PV system failures. Only about 1 in 2000 modules will fail during their warranted 25-year life. The system components most likely to fail are the ones with complex electronic circuitry.
Voltage drop (VD) is the loss of voltage in a circuit due to the resistance in the electrical circuit. To determine the amount of voltage lost in a circuit, we need to look at three parts: 1. Resistance of the conductor in Ohms (Ω), 2. The length of the circuit conductor, 3. The current flowing through the conductor. A forth component is to compare the VD to the operating voltage in the circuit to see the percent of voltage drop.
The short answer is yes since electrical utility companies generate a portion of their electrical energy from solar energy; indirectly everyone is a solar PV customer if they purchase electrical energy from one of these utilities. The better question is who is a direct customer of a solar energy system; the type that will offset or replace electrical energy that would have been purchased from an electrical utility.
Overall, the benefits of NABCEP certifications are to the industries they serve. The North American Board of Certified Energy Practitioners (NABCEP) was founded in 2002 as a 501(c)(6) non-profit organization with the stated goal to develop voluntary national credentialing programs that will promote renewable energy, provide value to practitioners, promote worker safety and skill, and consumer confidence in the industry. But how does certification help your career? Consumers need to be confident of their choices.
The question of optimum PV array size is the first question to be answered when designing the PV system. There are several factors that have to be considered to arrive at the best size. The customer budget, the available area for the array and the purpose of the PV array are always primary considerations. The budget is usually the most flexible since the system can be financed. The second may be difficult to get around if the location options are limited and restrictive. The third part is where most mistakes are made. There are generally two types of systems, (1) stand-alone and (2) utility grid interactive.
Your home’s overall energy efficiency is not as exciting to think about as a solar PV system, but it is much more important in most cases. Solar PV systems are getting more affordable, but that doesn’t help much if the overall energy consumption is higher than it needs to be. An energy efficient home will require about half the PV system size as a home that is not energy efficient. There are several low cost improvements that can improve energy efficiency; there are also many improvements that require an investment but provide good return on the investment.
The solar workforce in the U.S. has grown by over 160% since 2010 for a little over 93,000 to well over 250,000. Solar accounts for less than 2% of all electrical energy generation in the U.S. However, the solar industry employs twice as many workers as the coal industry, almost five times as many as nuclear power, and about the same number as the natural gas industry.
The term net metering has several definitions and interpretations. There is one most of us agree on as the standard model – the owner of a solar PV system may offset up to 100% of their electrical energy usage during the course of any one-month period at the retail rate. This is the one that solar contractors and customers like but it is also the one that utilities would like to see go away. There can be some drawbacks for the customer under this NEM.
No one wants a poor PV system installation, but it happens from time to time. The good news is it’s 100% preventable but you should first understand the causes of a bad installation, and then learn how to prevent it. We tell you how.