Solar systems usually don’t produce enough electricity for an average home or business in the Midwest so a back-up source of electricity is generally required. In Columbia, a customer can sign up for net metering, which allows the solar producer to either sell any excess electricity generated from the Photovoltaic system or buy electricity when it is needed.¦Yan Lu

COLUMBIA — In 2007, Andy Guti installed nine solar panels on his old house in northeast Columbia and immediately began to see a drop on his utility bills.

Guti was the first customer in Columbia to join the city's net metering system; for several months, his residential utility bills were as low as $15 per month.

"The first few months we had them, we generated more electricity than we used," he said.

Since the city first developed solar projects in 2007, both solar energy production and solar energy demand has increased, said Connie Kacprowicz, spokeswoman for Columbia Water and Light.

According to the city's 2011 Renewable Energy Report, the amount of solar energy increased from zero megawatt-hours in 2007 to nine megawatt-hours in 2010 — almost enough to power an average household for one year. Customers like Guti have contributed to that energy production.

Columbia started offering a net metering system for electric customers interested in private renewable energy systems four years ago, Kacprowicz said. Residents can sign an agreement with the city and install solar panels on private property. The city keeps track of the amount of electricity being produced and consumed and bills the customer for the difference at the end of each month.

Currently, the city has agreements with three residents.

"From a utility standpoint, solar is great because it produces a lot of electricity in the summertime, when demand is high," Kacprowicz said.

But the cost of solar panel installation is still steep, she said. "That's why you have incentives to get people to do it."

Solar panels cost about $14,000 to install, Guti said. But his motivation was simple: He was interested in energy efficiency and concerned about the environment. He wanted to reduce his carbon footprint.

Guti said that once the solar panels were in place, he could see the difference right away, even though he only used the house he owned as an office and consumed little energy.

For an average household, however, there could be even bigger savings.

Last summer, Joyce Pfaff bought Guti’s house and moved in. She said her electric bills were much less compared to what she paid before.

"Last month, when it was so hot, and I had air conditioning on every day, my electric bill was $54, and that included tax," Pfaff said.

She said she used to have set money aside to make sure she could cover her utilities.

"I'm not even worrying about that now," she said. "This is wonderful."

Because the technology is still expensive, installing a private system is voluntary.

"If you are going to install solar at your home, you probably are doing it because you want to do it for the environment," Kacprowicz said. "Not so much to save money."

Aur Beck owns Advanced Energy Solutions, an Illinois-based company that provides solar installation in eight states. Beck, who helped install solar panels on Guti’s house, said that for every home project he has helped set up in Missouri, the resident had seen payback within six years.

Beck said that Columbia has the most forward-thinking utility services in the Midwest.

"They had net metering before any utility in the Midwest," he said. "And they implemented programs almost two years in advance of everyone."

Private businesses produce solar energy for the city through the Solar One program, which has a goal of producing 1 percent of Columbia’s electric portfolio from solar power by the year 2023, Kacprowicz said.

Under Solar One, businesses buy and install solar panels and sell the energy that is generated to the city. The electricity goes into the city's power grid and is then divided into 100-kilowatt hour blocks to sell.

In November 2008, Columbia Water and Light started two Solar One projects — the West Ash Pump Station on Bernadette Drive and the Quaker Oats plant on Route B. Each is expected to produce 70 blocks annually, Kacprowicz said.

The city has also contracted with Bright City Lights, a retail store at 1400 Heriford Road.

Kay Wax, owner of Bright City Lights, said her store installed 24 solar panels in August 2010. She said she hopes to break even in 10 years.

"I had to get a loan for all of the panels and labor," she said.

Wax said she joined the program because she believes in sustainability and protecting the environment.

"I think the message is, we are trying to get people to think of alternative energy sources," she said. "That's what my purpose is."

As a result of the additional solar projects, 250 additional blocks of electricity became available in 2010. So far, 240 of these have been sold, Kacprowicz said.

In 2010, the city signed a lease with an Omaha-based company to provide another source of solar energy. Free Power installs solar panels on sites developed by the city as an inexpensive energy alternative.

"They sell us the energy for $54 per mega-hour, which is about the same cost as new coal fire resources," Kacprowicz said.

However, the city's investment in future solar projects will depend on cost more than anything else, Kacprowicz said.

"The hope is the cost will go down," she said. "If it goes down, it will be a more valuable energy source."

Electricity produced by coal-fired generation units is apt to be with us for some time to come. If we shut down all or even most of those units tomorrow there will be insufficient electrical power in the grid to meet commercial, industrial and residential demand. We may not like it, but that's how it is.

(Well, it makes some folks happy. Coal mines, for one, and several domestic railroads that make a good living hauling coal from mines to power generation plants.)

The US currently gets about 8 TeraWatts per year from fossil fuel sources. Raw solar irradiance at surface for lower 48 is ~544 TeraWatts per year. At current mass-production panel efficiencies, the US would need to cover ~3-5% of it's land surface with solar PVC to completely replace the amount of energy we get from fossil fuels.

Then, we'd just have a lot of problems to solve with intermittency, storage, transmission, and consumption.

Getting houses set up with the grid-tie to distribute that 3-5% surface area coverage on rooftops is actually a very effective and useful way to solve part of the 'where' part. But we'd still need massive storage and distribution systems to really make it work, and a conversion of most of our transit systems to electric power. Daunting tasks, all of them.

"Why wouldn't the table include coal, since that's how our power is generated in Columbia?"

I believe the table was just considering renewables. You are correct about the cost of production from coal - that's why we use so much of it.

Derrick Fogle wrote:

"At current mass-production panel efficiencies, the US would need to cover ~3-5% of it's land surface with solar PVC to completely replace the amount of energy we get from fossil fuels."

You actually wind up needing more of it than that, because without large amounts of storage, there will be times that one part of the country has to power all of it. This means that most of the country (or at least the sunny areas) will have to install solar well above their needs and either store or simply waste the excess.

I'm increasingly of the opinion that we will not be able to afford any large scale conversion to renewables without a real breakthrough in either efficiency or cost. Three terawatts of panels, at $2.00/watt, is $6 trillion dollars, and that doesn't include all the extra transmission lines, energy storage (pumped hydro costs anywhere from $1.50 to $3/watt), controls, etc, etc. Plus, the world only makes about 10-15 GW of panels/year, so were talking decades to centuries to be able to do it. Plus Germany's push for renewables will probably drive up panel prices in the near term (and make them dependent on Russian natural gas).

It actually may be more efficient of resources to install local, self contained "microgrids" that only rely on grid current for backup in case of extended cloud (or calm in the case of wind). Transmission lines eat up as lot of resources.

"Beck, who helped install solar panels on Guti’s house, said that for every home project he has helped set up in Missouri, the resident had seen payback within six years."

Without the very generous subsidies that solar enjoys, the payback period would be closer to 15 years.

Neither of my off grid systems will ever pay for themselves, because of the cost of replacing the batteries every 7 to 10 years. However, grid tie systems do not work if the grid is down, where mine does. I consider it paying my electric bill in advance for the rest of my life.