How Much Electricity Will PV Solar Make In Chicago Each Year?

Calculating the electricity output of solar PV panels is very important and should be looked at and discussed with your PV installer prior to making any decisions.  Photovoltaic panels can produce high amounts of electricity, but there are also many ways that they can lose efficiency and then lose output and value too.

Chicago, IL and Solar Potential

Chicago is one of the cities that is growing rapidly right now with solar power projects.  There has been many different initiatives from the local and state government to promote clean energy and the residents are taking notice.  Still though, everyone needs to pay attention to the science of PV solar and needs to understand the limitations and the expectations that solar can provide.

Estimated Electricity Production from PV in Chicago:

Calculating the electricity production numbers requires an understanding of the average sunlight hours per day each year in any given area.  For Chicago that amount is about 4.8 average hours of sunlight per day per year.

If we look at one average size solar panel of 180 watts DC, we can now calculate the expected electricity.

Here is the math equation to calculate Electricity Production from PV in Kilowatt Hours:

180 watt DC * 4.8 = 864 watts DC each day

After a 15% electricity loss in converting to AC(Alternating Current) the above amount equals: 734 watt hours.

So in one day, 1 solar panel would produce about .734 kwh

Over the course of a year, this would equal = 267 kwh each year.
Summary of Solar Panel Electricity Each Year in Chicago:

One 180 watt solar panel can produce about 267 kilo watt hours (kWh) per year in Chicago, IL.

PV Solar panels in Chicago, IL

Eligible Renewable Projects for Illinois State Funds:

The state of Illinois developed a Renewable Energy Resource Program to help several different types of projects come to life:

• Photovoltaic Solar Panel Systems
• Solar Hot Water Systems
• Solar Space Heating Systems
• Wind Systems
• Solar Pool Heating Systems

Illinois State Incentive Amounts (In Dollars and Percentages of Project Costs)

• All residential and commercial projects were eligible for funding up to 30% of the project costs.

• All non-profit and public projects were eligible at 50% of the total project costs.

• The MAXIMUM solar rebate or wind power rebate for any of these projects has a maximum of $50,000

• The minimum size of a solar panel system had to be at least 1KWH which is an incredibly small system

Major benefits of this Generous IL State Rebate for Solar:

The Illinois solar rebate program has allowed many homeowners who were interested in solar energy to actually make it a reality.  Although the funding has since dried up for this program, it helped to pay for a large part of many system owners up and running solar panels.  Another huge benefit with regards to this particular state level incentive program is that the Renewable Energy Credits(REC’s) are still owned by the energy producer which in many cases is the small business owner or homeowner.  This is considerable because the value of the REC’s will likely be increasing over time and further allow the owner of the system to help finance or pay for the up and running system.

Current Status of the Illinois Solar Rebate Program:

At the moment(December 2010), all of the funding for this incentive program has been used up or is already claimed.  Once the funding comes back for more systems, there should be an increase in the number of applications from solar system owners which can be accepted once again.

Illinois Laws Concerning Solar Panels

State Law in Illinois is very good for people who want to own a solar system.  The law is very clear and to the point with regards to the rules and regulations that must be used by both condominium associations and other types of homeowner groups.  The rules also apply for people who might be lucky enough to live on or near a golf course or within a country club type of setting.  The rules is that homeowners and property owners are allowed to have solar panel systems and there are literally no exceptions.  The only part of the rules in the state of Illinois that associations or governing boards may put in place on people wishing to have solar systems is they can enforce rules on the exact location a system should be located at.  But, to the homeowner’s defense, if for example a homeowners association tries to tell someone to place their solar system in a location that negatively impacts the production of electricity or the output of the system, that would be again violating the laws of the state.

Congrats to Illinois and the Governement’s Stand on Solar Panel Rules:

This law has already been tested several times in the state of Illinois and every time the homeowner has prevailed.  Not only does the law prevent housing authorities from controlling and mandating that residents use power from the utility companies, the law also clearly explains that the little rule making the associations do have in Illinois is very little at that.  This is how the solar laws for homes should be.  It should be everyone’s right to have solar power and to place a solar system in a location that is going to produce the most energy.  The hang up that neighbors have about rules on where solar panels can and can not be placed hopefully will eventually just fade away.

Today we are going to find out how many kilo watt hours of electricity a PV solar system will produce if it was located in the city of Chicago, and of course if there was no shade on the PV system.

There are a few different ways to figure this out. This post will explain the simplest way to determine the solar energy production.

-The size of the solar system that we will be measuring is going to be a 5.0 kw PV solar system. That is equal to a 5000 watt solar system because there are 1000 watts in a kw.(1000×5= 5000watts=5kW)

-The location that we will use to come up with an average sunlight hour number is Chicago, IL. The average number of sunlight hours there is about 4.4 hours per day.(Of course there are many more hours where people would consider it to be “light out”, but all “light out” hours are not equal, we need to average number of hours that solar panels would operate at maximum efficiency, othewise the math that would be needed for “its light outside hours” gets very complicated and returns the same answer.

-We will use an energy loss amount of approximately 15% when the current goes from DC to AC(yup, there is always going to be some energy loss in the form of heat mainly, and right now with todays technology(which is really good) the energy loss is unavoidable.)

So, here is the equation:
5000 wattsDC X 4.4 hours/day = 22,000 watt hoursDC/day = 22.2 kwh/day on average in DC

Next, we will factor in the energy loss of 15%:
22.2kwh X .15= 3.3 kwh of lost energy in the conversion to Alternating Current

Next we will figure out how much AC current is left to use:
22.2kwhDC-3.3kwh(lost)= 18.9 kwh AC produced per day

Next, we will figure out how many kilo watt hours are produced each month on average:
18.9 kwhAC/day X 30(days in the average month) = 567 kwh AC produced on average per month

Next, we will figure out how many kilo watt hours are produced on average per year:
567 kwh AC per month X 12(moths in the year) = 6,804 kwh per year

SO, in Las Vegas, Nevada, you could expect a 5.0 kwh solar system to produce approximately 6,804 kilo watt hours of electricity per year.

One of the assumptions is that there would be no shade hitting the solar panels as that would adversely affect the electricity production. Just think of it like this, if there is shade from a tree hitting the solar system for 20% of the day, the electric production of the solar panels is likely to be exactly 20% LESS than the number above, that’s a BIG BIG difference, and something you want to avoid.

When you are buying a solar system in Chicago, be sure to ask the solar professional to explain the expected sunlight hours to you. This is quite possibly the most important bit of data you need to know before writting any checks.

Also, since Chicago is a very progressive city in some respects, you might just luck out and run into a great Chicago solar incentive program when you are speaking with the local solar installers. Make sure to ask them what the current incentives are, it can save you bigtime on the solar purchase.