How to Make Your Electric Meter Run Backwards

What is a solar grid-tied system?

How fast will a grid tie system pay for itself?

Will a grid tied solar system provide me back up power if the grid goes down?

Will my utility company do net metering with my grid tied solar array?

Will hail damage solar panels?

Could a strong windstorm blow an array of solar panels off my roof?

I can't afford a system large enough generate all my power, so why bother?

If I buy a small grid tie solar system now, is it difficult or expensive to add on to it every year or at a later point?

What about solar shingles?

What are Thin Film Laminate Panels?

What about wind power?

What are solar micro inverters?

What is a solar grid-tied system?

Solar grid tie systems allow you to to generate your own renewable, non-polluting energy and distribute it back on to the electric grid. Granted, unless you've over-sized your system, you are only likely to be turning your meter backwards in the spring and fall, but the concept is the same. Consumers today have the opportunity to make their utility companies distribute clean solar and wind generated power, regardless of how unmotivated the utility company may be to do so.

Grid tie electric systems consist of two primary components. The first is the solar electric or photovoltaic (PV) panel array. The other is the grid-tied inverter. The inverter is responsible for converting the DC electricity being generated by the solar panels into the AC electricity that your home uses.

How fast will a grid tie system pay for itself?

A grid tied solar system will not pay for itself nearly as fast as a solar hot water system. Frankly, the average price charged by Oklahoma electric utilities is close to being the cheapest in the nation. But ask yourself, what is it worth to you to be using power generated from clean, renewable solar energy instead of from non-renewable and polluting coal, natural gas, and oil? What is it worth to you to know that you are have taken a major step to help reduce the threat of global warming? When future generations look back on our society today, suffering from the impacts of present society's indiscriminate use of it's most limited and precious resources, do you want them to remember you as part of the problem, or part of the solution. This is not to say that you must have solar panels to make a difference. It is simply one way of many, albeit a significant one.

Will a grid tied solar system provide me back up power if the grid goes down?

Not by itself. To have back up power you can use a battery bank and a separate back up power inverter for this task. Normally backup power systems are designed to supply backup power to critical loads (like refrigerators and lights) which are routed to a separate sub panel in your house. A battery backup system is actually something that can be installed without having any kind of solar or wind power source present. It works by charging a bank of batteries when the grid is up and drawing power from the batteries when the grid is down.

Will my utility company do net metering with my grid tied solar array?

Unless your power company is an electric co-op, they are required by law to do net metering. Fortunately most larger-sized electric co-ops do support net metering anyway, but some smaller ones may not. Sometimes this is because they have not had any customers ask them to. If your local power co-op does not support net metering, you might see what it would take to get them to. It actually requires very little on their part, since most electric meters will run backwards with out any modifications required.

Will hail damage solar panels?

The glass used in solar panels is high strength tempered glass that is roughly as strong as a car window. If it were to hail hard enough to where it breaks automotive glass, then your panels might be at risk of damage, but this kind of storm doesn’t happen very often. If you add a purchased solar array to your homeowner’s insurance policy, hail damage should be covered. Thin film laminate panels, which don’t involve glass in their design, are one option you can choose to alleviate this concern.

Could a strong windstorm blow an array of solar panels off my roof?

Pre-engineered racks, mounting, and anchoring systems are engineered to withstand at least 110 mph wind speeds.

I can't afford a system large enough generate all my power, so why bother?

Has the miles per gallon of a vehicle ever been an influence for you when purchasing a car or truck? When you were looking at the MPG ratings and you couldn't find a car for sale that didn't use any gas at all, did you think “Well, I can't find anything that will prevent me from buying gasoline, so if I'm going to be supporting big oil anyway it doesn't matter how inefficient it is.” If you’re reading this, probably not.

Think of your house as something with an efficiency rating like a car. Just because new houses aren't advertised with a value on them telling how much power they consume per occupant, doesn't mean that statistic isn't there and isn't important. Wouldn't the possibility of converting your house from a 25mpg home into a 45mpg home be something worth considering? This is essentially what you are doing when you make energy saving improvements to your home and/or install different means of harvesting free and renewable energy... you're improving its fuel efficiency.

If I buy a small grid tie solar system now, is it difficult or expensive to add on to it every year or at a later point?

It is actually quite easy once the components of grid tie system are installed to add on to it incrementally. There are several different means of expanding a system: You can purchase a larger capacity inverter (in relation to the size of your PV array) up front. Or you can swap out your inverter for a larger one at some point in the future and receive credit back. Or you can use the new micro inverter products which totally eliminate all the sizing considerations that central grid tie inverters carry.

What about solar shingles?

Solar shingles are a type of thin film laminate solar panel that mimics the appearance of a regular asphalt shingle and can be installed in a patch on your roof among your regular shingles. But there is a major price premium to pay both for the product and the installation of solar shingles. The typical installed cost of grid tie solar systems ranges from $6.50 to $8.00 per watt. The installed cost of a system using solar shingles could be as high as $12 per watt. If you have a home owner's association saying only solar shingles are allowed in your neighborhood, there is probably an alternative involving panels on the back of your house or in your backyard that can be negotiated that would have no visibility from the front of your house.

What are Thin Film Laminate Panels?

Thin film laminates are now making a major debut in the solar industry with prices comparable to traditional panels now for the first time. Unlike traditional PV panels which are made with silicon, thin film laminate panels by layering several different microscopically thin metal oxides. These panels have several advantages over traditional panels:

-Can be made with no glass, adding hail resistance and making them lighter weight.
-Have better low light performance, resulting in power generation even when its cloudy and in indirect light.
-Use less energy to manufacture than silicon panels

Traditional panels have the advantage of a smaller surface area per wattage rating. In other words, a 64 watt panel silicon panel is smaller than a thin film panel of the same wattage.

What about wind power?

People like wind power. There's a definite cool factor involved with seeing a wind generator frantically spinning around, showing in a clearly visible way how it's turning something as common as wind into something as useful as electricity. And Oklahoma and Texas are notorious for as windy states. But before you decide that wind is a better choice than solar, consider the following:

- Despite the most people thinking that Oklahoma is an extremely windy state, the majority of locations in Oklahoma have a wind speed that is considered to be merely average in the wind industry. However, certain areas around the Wichitas, the Ouachitas, and the northwest part of the state have very high average wind speeds, which make wind an option worth considering.
- To get the performance advertised by the manufacturer, a tower at least 60 feet is generally needed to get high enough above surrounding buildings and trees. This is taller than the zoning requirements that most homeowners must follow.
- Solar power components have warrantees that are two to three times longer than wind power components. And with solar, if something does need attention it's within easy access and not on top of a 35 to 120 foot tower.
- Residential home energy demands are closely matched to the sunniest times of the year. Conversely, the hottest and most energy consuming months like August are the least windy. And the windiest times of the year normally occur in the spring and fall when the energy demands of your home are the lowest.

What are solar micro inverters?

A new product that has come on to the market is the Enphase micro inverter. Instead of having a central grid-tied inverter, this product involves having one small inverter for each panel on the roof. This allows for several unique advantages:

-Allows unlimited expansion of system without being limited to the capacity of the previously installed inverter(s)
-Panels can be installed in any increments rather than in banks of 4-9 panels at a time.
-System add-ons to not require that new panels exactly match the brand and model of the old panels.
-Monitoring tools that go along with the Enphase inverters show real time output performance data and animations of past performance online. This makes it immediately clear if there is a problem with one of the panels, or if there is shading affecting part of the solar array.
-Greater efficiency ratings that most other central grid tie inverters.
-They are more cost effective than most other centralized inverter systems for arrays less than about 2 KW in size. Even for larger systems, customers may find the advantages they offer well worth it.

For more information along with some really good demo videos, visit Enphase Energy

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