Solarithmetic

Via NewWest, an interesting example of rooftop economics from a residential solar perspective in Montana:

Consider that the average US home uses 9000 kWh (kilowatt hours) of power per year.  This is roughly 26.5 kWh per day. For example’s sake, we’ll say 25 kWh, which would be easy to obtain with minor energy retrofits.  If you figure that we have, on a annual average in Western Montana, 5-hours of sun per day to make energy from, that would mean we’d need to produce 5 kW of energy from that system, per hour, to get to 25 kWh.

5 kW x 5 h = 25 kWh

Now consider that the average panel produces 235 W.  This would mean that about 4.5 panels would be needed to produce 1 kW.

235 W x 4.5 panels = 1057 W
1000 W = 1 kW = 4.5 panels

So, to get to the 5 kW system we’re looking for, the average system would require 23 panels.

4.5 panels = 1 kW
23 panels = 5 kW

Now, most folks are not interested in offsetting 100% of their energy quite yet.  Here in Missoula we have annual net metering.  This means that you are assessed a bill each month depending on how much energy your system will put back in the grid (i.e. in January that might only be 10% and in July it could be 120%).  At the end of the year your total usage and production are assessed.  If you produced a deficit of energy, you will already have paid that amount through your monthly billing.  If you produced a surplus, well, you’re neighbor thanks you for putting clean, solar energy back into the grid.  But, at this point, Northwestern Energy doesn’t pay you back.  That’s not to say they won’t someday, with energy rates increasing at 4.4% on average.  However, since they currently do not pay you for your surplus, we usually design and install systems that cover 90% or less of your annual energy needs.

So, back to the example above.  Take the 5 kW system.  Let’s say we only want to go with partial coverage.  We’ll use a 2kW system as an example, as this is the smallest system that gets you the full $6k NW Energy grant. With a recent drop in hard costs of nearly 25%, we’re looking at $6/W installed:

2000 W x $6/W = $12,000.

As a company with a NABCEP Certified Solar Installer, SBS is one a few companies in the state that qualifies for special $6,000 grants from Northwestern Energy for Solar PV installs. We allocated our first round of grants for 2011 and in the process of getting our second round in your hands.  Our goal is to have them all in install mode by Halloween.  If you have been considering Solar PV, this sort of assistance really starts to make it affordable, especially coupled with State and Federal Tax Credits.

Now, apply the $6000 Northwestern Energy Solar PV Grant, 30% Federal Tax credit, and $500 per MT tax payer credit (so, $1000 for most households):

$12,000 (gross)
– $6,000 (NW Energy)
– $1,800 (30% Federal Tax Credit)

- $1,000 ($500/person MT Tax Credit)
_____________
=$3,200 (net)

This is, of course, just an example.  But is a good indicator of what’s out there today.  If you don’t have tax liability this year, the tax credits can be carried forward for up to 5 years.

An additional program that can really make this all come together in the MT DEQ revolving loan fund for renewable energy.  With this program you can finance up to $40,000 over 10-years at only 4%!  This is the final piece of the puzzle for many of Montanans seeking renewable energy alternatives.  It works in conjunction with the above federal and state tax credits and can be used for the gross amount of the system.  You can also add 20% into that gross cost for energy efficiency measures.

We are lucky that the State and Feds decided to keep our renewable energy tax credits in play.  These incentives will make or break the affordability of these systems and the healthy growth in the green energy sector for our state.  At points this spring it looked like we may loose some of these incentives.  While we have the incentives monies in play, 2011 is looking like a great year to get into solar.



This entry was posted on Thursday, June 2nd, 2011 at 6:52 pm and is filed under Uncategorized.  You can follow any responses to this entry through the RSS 2.0 feed.  You can leave a response, or trackback from your own site. 

Leave a Reply

You must be logged in to post a comment.


About This Blog And Its Author
As potential uses for building and parking lot roofspace continue to grow, unique opportunities to understand and profit from this trend will emerge. Roof Options is committed to tracking the evolving uses of roof estate – spanning solar power, rainwater harvesting, wind power, gardens & farms, “cooling” sites, advertising, apiculture, and telecom transmission platforms – to help unlock the nascent, complex, and expanding roofspace asset class.

Educated at Yale University (Bachelor of Arts - History) and Harvard (Master in Public Policy - International Development), Monty Simus has held a lifelong interest in environmental and conservation issues, primarily as they relate to freshwater scarcity, renewable energy, and national park policy. Working from a water-scarce base in Las Vegas with his wife and son, he is the founder of Water Politics, an organization dedicated to the identification and analysis of geopolitical water issues arising from the world’s growing and vast water deficits, and is also a co-founder of SmartMarkets, an eco-preneurial venture that applies web 2.0 technology and online social networking innovations to motivate energy & water conservation. He previously worked for an independent power producer in Central Asia; co-authored an article appearing in the Summer 2010 issue of the Tulane Environmental Law Journal, titled: “The Water Ethic: The Inexorable Birth Of A Certain Alienable Right”; and authored an article appearing in the inaugural issue of Johns Hopkins University's Global Water Magazine in July 2010 titled: “H2Own: The Water Ethic and an Equitable Market for the Exchange of Individual Water Efficiency Credits.”