Iowa City to convert streetlights to LED over next four years

IOWA CITY - The City of Iowa City and MidAmerican Energy have signed an agreement to convert the city's roughly 4,000 street and pedestrian lights to light-emitting diode, or LED, units over the next four years.

Switching to LED lighting - happening in cities across the state - is expected to increase visibility and safety for drivers and pedestrians, while saving the city money in energy costs in the long run, said Brenda Nations, Iowa City sustainability coordinator.

'It saves both money and energy and saving energy will lower our greenhouse gas emissions,” Nations said. 'Over the course of the next few years we hope to have all LED streetlights.”

Funding for the LED conversion became available with about $530,000 the city overpaid on its MidAmerican Energy bill for streetlights from roughly 2004 through 2014. That money was reimbursed last year and earmarked for the LED streetlight project.

The city already has an agreement with MidAmerican Energy that includes LED lighting in any new light structures, she said.

Nations said the city has budgeted $50,000 this year for that effort and an additional $75,000 per year for the following four years. Those numbers are estimates as officials are still determining pricing and the replacement process.

The conversion effort will take place on two fronts, with MidAmerican agreeing to convert the 2,600 lights maintained by the energy company from either high pressure sodium or metal halide lights to LED. That conversion will come at no cost to the city and the use of LED lights should save the city roughly $100,000 a year in utility costs.

The remaining 1,400 lights owned and maintained by the city also will be converted to LED by the city's streets department.

These lights, which are found in parking lots, on the pedestrian mall or at downtown intersections, are unmetered and the city is charged per light type, rather than by usage. Nations said the cost savings on these lights is undetermined as city officials don't yet know the utility company's tariff for customer-owned LED lights.

Ashton Newman, media relations representative with MidAmerican Energy, said Iowa City's effort is part of a companywide transition of roughly 100,000 of the company's streetlights across multiple cities from high pressure sodium lights to LED units.

'Participating cities will be transitioned to LED streetlights concurrently over the next 10 years,” she said in an email. 'As (high pressure sodium) streetlights fail, they will be replaced with LED fixtures.”

Last year, City Manager Tom Markus estimated the LED project would cost up to $350,000 and pay for itself in a little more than three years once they're installed.

LED lighting comes with a higher upfront investment - an LED unit can cost hundreds more than a typical $20 high pressure sodium light - but lasts longer, creates better visibility and uses less electricity.

According to the U.S. Department of Energy website, the use of LED lighting on roadways provided an energy savings from 26 percent to 57 percent compared to high pressure sodium lighting.

Jon Resler, Iowa City's superintendent of streets, traffic engineering and solid waste, said switching to LED is rarely as easy as changing a light bulb, but rather can require retrofitting or an entire replacement of the lighting fixture.

Officials will be exploring their options to determine the best approach for LED conversion.

'It's something we have to really look into to get the most bang for our buck,” Resler said. 'First step is really determining how we perform the upgrade.”

In Cedar Rapids, officials with Alliant Energy have been working to convert their streetlights to LED since 2013.

In April, an Alliant spokesman said the energy company had replaced 20,000 lights out of an estimated 100,000 in Alliant's Iowa service area, which stretches across most of the state.