Renewable Energy Archive

Solar homes sell 20% faster, for 17% more

Sunday, October 31st, 2010

It has been over 10 years since we've seen a new report on the relative benefits of selling a house with solar installed. Homeowners pondering installing solar frequently ask whether the resale value of the house will be positively effected. So we were glad to see this new comparative study from the National Renewable Energy Laboratory which reports benefits to resale value and a reduction in time to sell. The link below is a concise summary of the report from Susan Kraemer, and includes a link to the report itself

Solar homes sell faster.

Read the original post at The Carbon-Free Home blog.

Stephen and Rebekah Hren are the authors of The Carbon-Free Home and A Solar Buyer's Guide for the Home and Office.

Solar Buyer's Guide Table of Contents

Wednesday, October 20th, 2010

Most solar books out there just focus on introductions to solar electricity. Ours provides a comprehensive overview of the three main solar technologies (photovoltaics, hot water, and heating), understanding financing, dealing with installers, and much more. Here's the Table of Contents to give you a better understanding:

  • CH 1: Types of solar
  • CH 2: What's appropriate for your site
  • CH 3: What's appropriate for your budget
  • CH 4: Getting ready for the installation
  • CH 5: Solar electric (PV) systems
  • CH 6: Solar hot water
  • CH 7: Solar heating
  • CH 8: Everything else under the sun
  • CH 9: The future of solar

Read the original post on The Carbon-Free Home blog.

Stephen and Rebekah Hren are the authors of A Solar Buyer's Guide for the Home and Office and The Carbon-Free Home, both available now.

Solar Power International 2010 Day 1: Lakota Sioux Leading Nation Away From Fossil Fuels

Tuesday, October 12th, 2010

Rebekah is spending the week nerding out on all things solar at Solar Power International 2010 in Los Angeles. She's picking one item as the "cool solar thing of the day" and blogging on Huffpo about it.

Henry Red Cloud is a respected Lakota elder and a fifth-generation descendent of the last Lakota war chief Red Cloud. Now he's fighting a new war against poverty and unemployment on the reservation and against our nation's dependence on planet-killing fossil fuels. For his sustained leadership in this field, Mr. Red Cloud was awarded an Innovation Award by the Interstate Renewable Energy Council.

Henry Red Cloud talks with Solar Energy International's Johnny Weiss after receiving IREC's Innovation Award on Monday evening.

Henry Red Cloud heads Lakota Solar Enterprises, a Pine Ridge, South Dakota reservation-based manufacturer that produces solar air heaters for local residents. In the past four years they've not only built and installed over 1,000 solar air heaters, they also created the Red Cloud Renewable Energy Center. At this facility, Native Americans from around the country can received training on solar technologies from other Native American trainers.

Read the original article on The Huffington Post.

Stephen and Rebekah Hren are the authors of The Carbon Free Home and, most recently, A Solar Buyer's Guide for the Home and Office.

Carbon-Free Military?

Tuesday, October 5th, 2010

Here's some news that we would hesitate to call "good" but is certainly ironic! The military, already hip to the reality of peak oil, is ordering less dependence on fossil fuels. They better be careful, because if we succeed as a nation to wean ourselves from those bad boys, we just might not need a military anymore.

Imagine if the $700,000,000,000 we spend on the military every year went to developing renewable energy at home rather than to the Pentagon, the 32nd largest consumer of fossil fuels in the world, above entire nations like Greece or Austria. All of a sudden, no need to have troops in Iraq, Kuwait, United Arab Emirates, Saudi Arabia, etc etc. All those brave troops could be up on our roofs here at home, installing solar, instead of dodging IEDs! And it just might be, just maybe, that if we didn't have our troops in 135 of the 192 countries across the globe, we wouldn't be seen as imperialists trying to dominate the world, and it wouldn't seem so worthwhile to send their sons to our country and try and blow us up. Crazy thoughts, we know.

This article appeared originally on The Carbon-Free Home blog.

Stephen & Rebekah Hren are the authors of, most recently, A Solar Buyer's Guide for the Home and Office.

Lots of Rooftop PV = Steady Power

Thursday, September 30th, 2010

One of the concerns with renewable electricity such as solar and wind is the variability of the power generated. We've always suspected that a diverse array of renewable energy installations would average out into a steady supply, and it's great news to see this confirmed with a recent study by US Department of Energy.

Rebekah up on our roof with the PV.

Turns out lots of small PV arrays on lots of rooftops over a large geographical area produces a relatively steady stream of juice. Imagine what the situation will be like once we have a smarter grid and a decent number of electric cars that need their batteries charged. It's not hard to imagine a setting for charging the electric car that helps even this flow out even more, taking advantage of large flows to increase the charge rate and keeping the juice out on the grid during the shady doldrums.

A few analogies spring to mind. The original thought of an leveling out from many multiple sources actually sprung from the idea of Hubbert's Peak, where the output from many small wells produces a fairly predictable and uniform bell curve. Also, tiny is mighty. The millipede has many small legs, and is very difficult to tip over.

Read the original article on The Carbon Free Home.

Stephen and Rebekah Hren are the authors of, most recently, A Solar Buyer's Guide for the Home and Office.

Farewell, My Lovely: Bidding Adieu to Our National Parks

Saturday, September 25th, 2010

We had an amazing trip this summer doing research for a new book. Along with visiting sustainability activists of all types, we had the opportunity to stay a few days in Glacier National Park, one of the most beautiful places in the world. We even got to see a mountain goat! Very exciting.


One thing we didn't see a lot of were glaciers. And you don't get a prize for guessing why we didn't! The fact is, they're melting, and not just a little bit, but like, all-the-way-gone gone. From 150 glaciers when they were first recorded in 1850 to just 25 today. That's right, over 80% melted. The last 25 are expected to have vanished from glacier-dom in ten years. Kaput. Over. No more glaciers in Glacier National Park within a decade. Take a look at the above photo taken in 1913 of Shepard Glacier, and compare it to the same place in 2005.


One thing they might want to consider is renaming it Rocky Mountain National Park, because we went to the park that currently bears that name in Colorado, and it's in mega trouble. Because of decades of drought and extreme heat, a variety of nefarious beetles have infested much of the ponderosa pines and other evergreens that used to make this one of the most beautiful places in America. In parts of the park 90% or more of the trees are dead, and entire ecosystems are in a lamentable death rattle. If someone had told us that a nuclear bomb had recently been dropped on this park, we would have believed them.

On some level, visiting these parks felt like saying farewell forever. If we are ever able to make it out to these wonderful places again, they will surely be even more severely compromised by our insidious addiction to fossil fuels. Living in America today has all the hallmarks of being married to an abusive alcoholic. We continue to destroy everything we love, even though the answer is so painfully obvious. Going straight today means utilizing renewable energy, incorporating permaculture principles like edible landscaping and eating local, and making difficult but ultimately fruitful and rewarding decisions like giving up one of the family cars and taking more mass transit and bicycling. Figuring out the path forward is not difficult, its finding the will to accomplish these things that is the challenge. The awesome thing is that embracing a sustainable life is a reinforcing positive cycle. Taking a few steps forward, like planting a fruit tree or hanging up your clothes to dry, brings cumulative rewards that illuminate the reasonable-ness and effectiveness of empowering yourself to break the fossil fuel habit. Positive energy breeds positive energy, in a positive feed back loop.

And we're going to need a couple of positive feed back loops that combat Global Climate Disruption, because we've created a few feedback loops that are making the situation just a trifle more dangerous than it already was (as if we needed that!). A big one on that score is the death spiral of the Arctic sea ice. The Arctic feels the brunt of global warming, and the temperature there is rising rapidly, leading to permafrost melting in Siberia, Alaska, and Canada. This is starting the release of massive amounts of methane, a very potent greenhouse gas. An educated guess is that to stop the runaway release of stored methane in the permafrost, we need to reach a peak in fossil fuel burning by 2015, and start a 3% reduction each year afterwards. With an oil peak either behind us or very near (as even conservative stalwarts like Forbes Magazine are acknowledging), this primarily means we need to start phasing out coal as a primary source for electricity as soon as possible. Fortunately, there's many ways to make this happen! All we need to do is make it a priority.

Read more about the Hrens at

Stephen and Rebekah Hren are the authors of The Carbon-Free Home, and the brand new book, A Solar Buyer's Guide for the Home and Office.

"Global Climate Disruption" and the Never-Ending Summer

Monday, September 20th, 2010

Glad to see that the White House has officially adopted Global Climate Disruption over Climate Change or Global Warming as the name for what is sure to dominate the news for the next few generations. We've been advocating this title for a few years now.

Since greenhouse gas accumulations can do things like melt the Greenland ice sheet and potentially bring the Gulf Stream to a halt, thus resulting in a new Ice Age for Europe and the Northern US, the term Global Warming can seem like a misnomer, even though generally speaking the planet is getting warmer. And Climate Change just sounds too natural and benign.

In our neck of the woods in the Piedmont of North Carolina, we're having another hellish summer that just won't quit. Some highlights:

- Rainfall eight inches below normal

- 84 days above 90F and counting. Before 2007 we had never had more than 72, but in 2007 we had 83. Next week, the official start of Fall, the predicted highs are in the mid-90s and no rain. The spinach I planted last week thinks I'm an asshole.

- 2010 tied with 1998 as hottest year on record for US.

Sorry to bitch and moan, but as a representative for all the plants outside, I had to say something.

Stephen and Rebekah Hren are the authors of The Carbon-Free Home, and the newly released A Solar Buyer's Guide for the Home and Office.