Installation and quick test:

$>  gem install equationoftime

$> irb

require 'eot'
# => true

@solar = Eot.new
# note: you'll see a lot more in the object than an id.
# => #<Eot:0x007f2b0ff26f70>

Set some parameters:

@solar.latitude = 40.7128
# => 40.7128

@solar.longitude = -74.0059
# => -74.0059

@solar.jd = Date.today.jd
# => 2457984
@solar.ma_ta_set
# => 3.9062095067660363 this is ma

Now get the times

@solar.local_noon_dt.to_time.localtime("-04:00")
# => 2017-08-18 12:59:49 -0400
@solar.sunrise_dt.to_time.localtime("-04:00")
# => 2017-08-18 06:09:35 -0400
@solar.sunset_dt.to_time.localtime("-04:00")
# => 2017-08-18 19:50:02 -0400

The local_noon_dt has taken into account the equation of time. This is the true solar transit time for your location.
Try the examples included with the gem.