Monthly Archives: July 2013

A Matter of Limits

I’ve written repeatedly about the incredible, almost staggering amount of energy in fossil fuels. Here’s why this is a problem—watch this amazing few minutes of video about how economic growth has lifted the world from sickness and poverty since the industrial revolution–

Wonderful, right? Hans Rosling is optimistic, and ends by excitedly saying “…everyone can make it to this healthy, wealthy world.” But, play this similar animated graph about world carbon emissions during that same time period, at Hans Rosling’s Gapminder site. In case you didn’t notice, they track together nearly exactly (and just look at China’s emissions on the rise toward the end—that’s the energy use that is powering China’s growth). Most readers probably know this already, but in case you haven’t thought about it recently—what our economy does, and is very good at, is turning energy into stuff. And, nearly all of our energy comes from fossil fuels. So, without exaggerating much at all, we turn fossil fuels into food, into belongings, into transportation and lifestyle. It is fossil fuels, nearly completely, that have powered humanity upward in the first video.

But herein lies the problem—though it’s only been three or four decades since we’ve truly realized it, the carbon emissions in the second graph are going to wreck the planet. So, thus the conundrum. We need economic growth to continue to lift the poorest billions out of poverty. BUT, the growth comes from energy, and the energy comes from fossil fuels, and we have to quit burning them so that we don’t commit planetary suicide. Continue reading

Urban Rooftops

On top of those skyscrapers...

On top of those skyscrapers…

First, I don’t want anyone to think I have been disparaging distributed, rooftop solar in some of my recent posts. Having solar on every roof would be a fantastic thing, and I think it’s a logical first step toward carbon-free power. PV panels are affordable, roof space is already present, and photovoltaic arrays don’t lose efficiency when they’re installed in smaller arrangements. But my point, every time distributed solar comes up, is that even if every rooftop were covered, this wouldn’t produce the amount of renewable power that we will need, and there isn’t enough rooftop space in cities to even begin to produce enough power to meet the demand of the people there. But, this doesn’t doesn’t mean it wouldn’t be worth doing—rooftop space in the sun is rooftop space in the sun. However, in cities, photovoltaics might not be the best use of this valuable real estate.

So, to back up a bit, let me sing some praises for solar hot water. In terms of efficiency, solar hot water collectors dramatically outperform solar photovoltaic panels. Capturing heat from solar insolation is just a fairly efficient process, compared to converting light into electricity. And, until just recently it didn’t make any sense, in terms of price, to install photovoltaics to make electricity that would then used to heat water. In recent years, however, heat pumps have become efficient enough, and PV systems have become cheap enough, that in many situations it might be a better choice to use photovoltaics and a heat pump to make hot water, instead of thermal collectors. (Good article here.)

Evacuated tube collectors for solar hot water.

Evacuated tube collectors for solar hot water.

However, regardless of the price of photovoltaics, it is likely that the best use of rooftops on large, tall buildings in the city will be thermal solar hot water, at least in any building where hot water or space heating is required. Though prices between the two systems are close to equitable today, the higher efficiencies of solar hot water make the physical footprints of such systems much smaller than that of  PV panels. My rough estimate is that the PV panels required to run heat pumps would take up four times the area of modern, evacuated-tube solar hot water collectors.

So, I suppose I have a rather small point to all of this—that down the road, we might need to use rooftops in cities for solar hot water. The footprints of such systems are smaller, and we could maximize gain from that limited rooftop real estate. Electricity can be produced remotely and then brought in on transmission lines; such a task with hot water would be fairly unworkable.

My second point might be that for some people in some situations, that advances in PV systems and heat pumps have made it less of a clear choice whether installing thermal solar hot water systems is the best way to use solar to heat water. But, as I was walking through small-town Vermont last week and pondering the fact that many people in town have quite-limited roof space with appropriate southern exposure, it could be that thermal systems, due to their smaller footprints, might remain a pretty good choice for many, whether they live in the city or not.

Blog note: Welcome, Australia, Canada, and Great Britain! My post about perennial agriculture seems to have been spread all over facebook, and I have been getting hundreds of views from all over the world, with clear groupings from these places. I write about my corner of the United States sometimes, but my focus is always on ideas and systems for the whole world, so it’s great to have you on-board. We’ve got a whole planet to fix, and we’re going to need people from every corner of it to get it done.

Image credit: ssuaphoto / 123RF Stock Photo
Image credit: packshot / 123RF Stock Photo

Good Job, Boston

Boston at night.

Boston at night.

Boston is beautiful. I’m here attending a conference about the economics behind the downfall of the Soviet Union. But, while here, I’ve also been thinking about the energy economics of big cities. The amount of energy being used here, on the face of it, is absolutely tremendous. Thousands and thousands of lights, vehicles, trains, ships, and all manner of other human activity, all involving power. BUT—per capita energy use and environmental impact, in cities, actually tends to run lower than that of people in rural areas. It’s not too hard to see why. My wife and I were just in a packed bar and restaurant, with all manner of lights blazing away. But, there might have been a hundred people in the room, and perhaps a hundred lights. That’s one light per person—a rate about five times better than the Bruhl family probably does on a typical evening at home. Likewise, the density of people in cities makes all sorts of activity less energy-intensive, when viewed on a per-capita basis. People commute less distance to work, or they walk or ride bicycles (the bike-sharing racks here seem to be doing a thriving business—good job, Boston), or take public transportation; all less energy intensive than driving a passenger car longer distances. I’ve seen ZipCars, too, and data from these programs show that people drive them quite efficiently. Because people are so close together, deliveries of goods happen more efficiently, as does the removal of garbage or recycling. (And, HUGE piles of recycling out in front of businesses in the historic district this evening, again, good job, Boston). Large buildings have proportionally fewer outside walls per square foot of space, and are dramatically easier to heat and cool than, say, single-family homes.

Worldwide, more and more people are moving to urban areas like this, and, as counter-intuitive as it would seem, this is good for the planet, because of these very reasons—it is easier to live with a reduced environmental footprint in an urban setting. Today, more than half of the world’s people live in urban areas (link). I’m not sure these huge growing cities qualify as “progress”, but it appears that the situation could be worse.

Another very important fact can be garnered from a walk through the city—there isn’t enough room here to create the amount of renewable power that the city needs. Everyone’s darling, distributed rooftop solar, might only be able to serve a fraction of a percent of the people here, and this is true of cites everywhere. People are close together; and there just isn’t enough roof-top space, or enough space of any sort, for that matter, for enough solar panels to supply the population. So here we have a huge city, where people are living close together in a way that is actually good for the planet, a city that will have to greatly increase their dependence on renewable electricity in the future as we move away from fossil fuel, that won’t be able to make their own power. It will have to come from the countryside, just as food and materials come from areas outside of cities. This will become a source of political conflict in the future, I’m afraid, as rural places balk at the solar farms and wind towers and hydroelectric projects that will be required.

Both of these aspects—the better efficiency of urban living, and the fact that their power will have to come from somewhere outside of cities—are both big-picture ideas that we need to keep in mind as we go forward. Personally, while I enjoy a short stay, I’ll choose to do my time in the least populated places I can find. But, I’m glad there are others who clearly prefer this. And if you choose to live in a city, Boston doesn’t appear to be a bad place to be.

Image credit: sepavo / 123RF Stock Phot


Wine--better for the planet?

Wine–better for the planet?

I’ve been pondering my last post,  about how perennial agriculture might save the planet. Or restoration agriculture, or agroforestry, or forest gardens; whatever you want to call it. I am pretty sure that the broad outlines of this idea are correct—we’re going to need some sort of polyculture for more symbiotic and diverse agricultural systems, and the use of perennials that only have to be planted once will help to save soil and energy, and all of the other positives I wrote about the other day. Extrapolating out from this results in some interesting ramifications, however. For example—wine or tea would be a better environmental choice than beer or soda, all else being equal. Wine is made from perennial plantings of long-lived vines, and tea from the leaves of trees, whereas beer is typically made from wheat or barley or some other annual grain, from fields that are tilled, with all the resulting soil erosion, fertilizer inputs, water contamination, fossil fuel use, etc., and soda is sweetened with high-fructose corn syrup, which is made with corn from similar fields in production facilities powered with coal. Likewise, a snack of nuts would end up being better for the planet than a bag of chips, maple syrup or honey better than cane sugar or high-frustose corn syrup, grapes or apples better than melons or cucumbers.

This also adds yet another notch in favor of grass-fed beef, which I already think is a good environmental and health choice. Properly-grazed fields improve the soil, and the meat from grass-fed beef has a nutritional profile more like wild game, which can’t be said for high-fat meat from grain-fed beef. But, grass pasture is also a perennial—such pasture doesn’t have to be tilled and sprayed or fertilized (the cattle do the fertilizing part all on their own). This perennial aspect only broadens the difference, in my mind, between grass-fed beef and your typical factory-farmed, grain-fed beef. One is good for the planet and reduced energy usage, the other a disaster. The same would hold true for cheese made from grass-fed cows, like that made by Steve Getz of Dancing Cow Farm in Bridport, Vermont. (photos, short article here), compared to cheese made with milk from confined dairy operations.

But, then I had to curb my enthusiasm. I’m not sure there are any hard-and-fast rules here. Even the restoration agriculture proponents grow some annual crops in the alleys between the trees. Plus, I garden organically in slightly-raised beds where the soil is mulched, and I guarantee that I lose zero topsoil in the process, nor do I have any other negative aspects. In fact, with mulch and compost, there’s no doubt that my soil improves every year.

Organic tomatoes--annual crops.

Organic tomatoes–annual crops.

So, it is too soon damn all annuals by definition, or to denounce beer as bad for the planet. A more nuanced view might be called for here. Perhaps this—organic is good, perennials are good, any farming where sustainabilily and the humane treatment of animals is a priority is good, and we need to buy our food, when we can, from people who produce it this way. Typically, this means buying from nearby, where you can go see for yourself. And, as always, it is good to support these operations with your dollars— Continue reading

An Important Piece of the Puzzle

“[The planting of crops that are annuals] destroys topsoil. Period.” –Mark Shepard, in “Restoration Agriculture”.

Replacement needed.

Replacement method needed.

I think I’ve found it, and I’m excited—an important missing piece to my mental image of where we are trying to get to. It relates to agriculture, and a problem that has confounded me for a while; years even. I touched on it last month in “One Tough Row: Agriculture“, with its lead photograph of soil erosion. To wit—I can imagine how to wave that magic wand around (yesterday’s post) and fix a lot of problems, but I’m not sure how to fix agriculture. How in the world do we make agriculture sustainable? How do we solve the fertilizer problem? How do we solve the erosion problems? How do we solve the pest-control problems, and how do we power future farm equipment without fossil fuel? How do we fix this system where it takes ten calories of fossil fuel energy to create every usable calorie of food? How do we solve the problem of diminishing groundwater? Of the cruelty, inhumane treatment, and disastrous environmental effects of factory farming? Of agriculture-related water pollution? The lack of bio-diversity? The crowding out of wildlife?

I’ve had some clues, some inkling of the direction to move in. I read about Joel Salatin’s farm in Virginia in “An Omnivore’s Dilemma”, by Michael Pollan, and my wife and I visited his farm a few years ago. He uses a form of polyculture—rotational grazing of livestock in a leader-follower system, and it enables him to raise beautiful beef cattle that are entirely grass-fed, eggs, chickens for meat (the chicken I had that day from his farm was the best I’ve ever had), and pastured pork in a symbiotic, harmonious system that out-produces neighboring farms by several-fold, uses no chemicals or pesticides, and rebuilds the soil from what Joel described as a “worn-out hill farm” with protruding rocks and barely enough grass to mow, to what it is today—one of the most beautiful farms I’ve ever seen, with rich soil and verdant grass.

Other clues—reports of farmers in Asia doing similar things with rotations of geese and ducks through rice paddies, with fish in the mix. A book just out by Judith Schwartz (interview here), “Cows Save the Planet”, about soil building through rotational grazing. Recent emails with a farmer in North Hero, Vermont, about soil-building through a combination of grazing livestock, subsoil plowing, and foliar feeds.

But there were holes in all of these. Grass-fed beef and fresh eggs are great, and healthy pasture is wonderful, but we need cereal crops to feed the world, or at least something like them. We need that massive production of carbohydrates, and of fats and oils, to help provide the energy for human life. And with polyculture in general, we have efficiency problems; as farmers step away from specialization, efficiency and productivity drop, and they have to know more and more about a huge number of subjects.

restoration ag coverBut then, last week at SolarFest, I attended a workshop by a young farmer named Josh Brill, entitled “Savanna and Forest Farms of the Future”. He is farming with a form of permaculture, and this system has the potential to solve every single one of the problems I listed above, and could even help reverse global warming. It could almost literally save the planet. His talk was fascinating, and it turns out that most of what he does and was discussing comes from the work of a farmer in Wisconsin named Mark Shepard, who has written a book called “Restoration Agriculture”. So I read the book. It’s important.

It’s also too much, perhaps, to capture in a single blog post, but let me try to impart the basics. To begin, take a look at the image at the top of this post of a field being disced. This is a form of how humans have done agriculture for 10,000 years—removing all other vegetation in order to plant seeds for annual crops. After you realize that there is a better way, however, the activity in this image starts to look like the agricultural equivalent of mountaintop-removal mining. We remove every living thing, and obliterate entire ecosystems, to prepare these large fields. Then, the wind blows away the bare soil, or the rain comes and washes it away. Then the planting begins, along with all of the problems I started this post with.

The “better way” is a form of permaculture using long-lived, perennial crops Continue reading

The Magic-Wand Question

turbine in field

Two of many required.

A number of you have responded to me, either on the blog or by email, about the wind issue, and the responses have run the gamut from strong support to strong opposition. I’m going to pause on the wind discussion, though, until after I go see the Lowell turbines, and even then I’m not sure I want to use this forum to get too deep into the specifics of a particular project. But I do want to think about the big picture, and I encourage everyone out there to do the same. In fact, particularly for those who find themselves in opposition to my position, I would like to know what your vision of a workable, realistic path forward is, using today’s technology (and I’m not being facetious when I write that). I often ask people, “If you had a magic wand and could rearrange the world, how would you fix it?”

With regard to energy, this is a tough question, even with a magic wand. When I wrote the other day that the amount of energy in fossil fuels is “staggering”, I wasn’t joking. Let’s just look at a very large wind turbine like the ones at Lowell. They generate a huge amount of power, over 3 megawatts per turbine at their maximum output. But, the actual amount of power generated by all wind projects fluctuates, because the wind doesn’t blow at full force all the time, and the total output is figured using a “capacity factor”, which is typically 20% to 40%. This is still a huge amount of power—let’s compare it with distributed roof-mounted solar arrays like the ones on my house. I have a 3kw system, but let’s just say for argument’s sake that I had a quite-large 10kw system. Solar installations have their own “capacity factor”. Just a back-of-the-envelope calculation—a 10 kw system in the Northeast, might only average 30 kwh of output a day over the course of a year, or, if you divide by 24, about 1.25 kw per hour, or a capacity factor of only 12%. It would take 720 such home installations to match the power generated by one turbine at Lowell.

But let’s compare a Lowell turbine to a coal-fired power plant. The average size of a coal-fired plant in the U.S. is 547mw. (Link to U.S. coal-plant data.) So although the Lowell turbines make a lot of power, it would take, in the real world, over 600 Lowell-sized turbines, to replace one coal-fired plant.

Brown coal plant in Germany.

Brown coal plant in Germany.

Continue reading

All Actions Have Consequences

Lukas Snelling, of Energize Vermont, sent me some files, and here are some pictures of what it takes to install utility-scale wind turbines in mountainous terrain. In this case, the project in Sheffield, Vermont, which is now completed.

Sheffield Vermont wind project, during construction.

Blasting cut.

Clear-cut for pad.

Clear-cut for tower pad.


Completed pad.

Completed pad.

Access to hilltop pad.

Access to hilltop pad.


So take these images, and imagine access roads that are probably four times wider, cuts that are four times deeper, and infills that are four times more massive—that’s the project in Lowell, with its huge 3-megawatt turbines. I don’t have any images of the Lowell project that I have the rights to include, but look at the pictures at these links-

Lowell access road, Lowell pad, Lowell infill for access.

I respect Lukas and his opinions, but we happen to disagree on this particular project. Continue reading


“We are all complicit. Have we all asked ourselves—are we driving the most fuel-efficient car we can afford? Have we taken steps to halve our own carbon emissions?” -Dr. Alan Betts, at SolarFest.

Early morning SolarFest

Early morning SolarFest

Your live, on-the-spot reporting from SolarFest here—many dreadlocks, much protest-music playing, sandals, Reggae music and Prius driving, henna tattoos, sprinkled with an occasional dose of suspicion of the government (ha, just like the far right), all wrapped up with a layer of techno-pop-Woodstock ambiance. But a great many products and workshops; ideas that could carry us a long way forward if they were applied across the board, from savannah farming to

Henna tattoos.

Henna tattoos.

carbon-zero houses and all manner of solar and wind products. But also on display—the problem we have that I’ve been writing about all along—many, many cases of the right hand not talking to the left. No one seems to have a workable master plan. On one side of the SolarFest lot, we have groups that are adamantly opposed to nuclear power, and particularly want the closure of Vermont Yankee. I’m not sure what their plans are to replace the power from today’s nuclear plants. My guess would be “consume less”, which, unfortunately, is everyone’s answer (I spoke with them after I wrote this, but I’ll save all that for future posts). Then on another side we have groups that oppose the new solar fields on Route 7 in Vermont, referring to this as “solar sprawl”. Then we have, which seems to oppose everything, and still other groups that oppose utility-scale wind here in Vermont. I spent some time talking to Lukas Snelling of Energize Vermont, a group that opposes all utility-scale wind on Vermont’s ridges. He had stacks of huge photographic prints of blasting and road construction and the huge access roads that are being built in Lowell, VT, in order to get the parts of these towers up the mountains. I will readily admit that the impact of these roads is substantial. These roads do not match one’s mental picture of “access roads”, they look more like four-lane highways prior to paving, complete with huge infills and equally huge blasting cuts, all in formerly pristine mountain landscapes. But as bad as this is, I’m also pretty sure this is a case of a failure to see the whole picture.

So let’s step back. How exactly are we going to save the planet? What exactly are our plans with regard to energy? The very short consensus by those who have looked at this—we’re going to need to phase out fossil fuels, and use power more efficiently, and, even with this (here’s the kicker)—double the production of electricity. Somehow. This after phasing out electricity generation from coal and natural gas . The amount of energy in fossil fuels is tremendous, almost staggering, and to replace it, even with serious conservation and efficiency, is going to take a massive effort.

Part of this will, and should, come from the one thing that everyone does seem to agree on—distributed, roof-mounted solar. I agree as well, for every roof to have solar on it would be a great start. But it wouldn’t be enough. The sun doesn’t shine at night, and, here in the relative north, it doesn’t shine much in the winter months. So, something else is going to have to take up the slack, and it’s going to have to be big, and it’s going to have to be carbon-free. And there’s no doubt in my mind that a big chunk of that needs to be from wind. Small-scale solar works, but small-scale wind doesn’t work nearly as well—there are huge economies of scale and efficiencies inherent in the larger wind projects. I will even allow that nuclear power might need to stay, at least for a while.

peace wallSo, more on this topic soon—Lukas is going to send me the files for some of his photographs of the Lowell wind project, and I’d like to post them; they are thought-provoking, and there is much to this that needs discussing.

But back to Solarfest—many good ideas, many dedicated people, mixed in with a few loonies and a few earth-types who could stand to shower a bit more often. It was all a bit messy, with not many clear answers, but perhaps that in itself makes it a miniature version of the problems we face.

Until next year.

Until next year.


It’s the Trend Lines that are Scary

water tap

Shortages ahead.

I hate to be bleak. I’m not a bleak person. But, I’m also a realist, and there is something real to worry about here. There’s a reason many people are concerned about the planet; it’s not just some fad, not just some way of life that lets people feel special or gives them some sense of unique identity.

Bottom line– what we’re doing to the environment now is bad enough, but it’s the trend lines that are scary. Nearly every key metric is still going in the wrong direction. The world’s population is still growing, despite a long-term trend toward leveling off, and every three days or so there are a million more mouths to feed on the planet (net increase). Worse, the current demographic situation has its own momentum—as all these young people grow up and have their own children, population will continue to rise for decades even if birthrates were at replacement levels (roughly 2.1 children per female). All of these present and future people will be trying desperately to live the best lives they can, and will continue to put extreme pressure on the planet.

So as we look out and see pollution, habitat destruction, species extinctions, and a host of other problems, we have to realize that these are all poised to get worse. And herein lies the real danger, that of cascading failure. It could play out in different ways, but the general patterns in such scenarios are all similar.

Let’s just play a little “what if”… Fisheries the world over are under intense pressure right now, and many have collapsed. What if continuing demand for seafood causes these collapses to continue, spurred on by population growth? We would then have a simultaneous situation of more food demand, and less food. People have to eat, so agriculture would need to take up the slack. But agriculture is also under pressure. The benefits of the Green Revolution have played out; average yields are no longer growing, and in some cases are falling, and all this as population is rising. So food in this situation becomes more scarce, and prices rise. Around the world, more land would have to be brought into production in response. But, virtually all arable land on the planet is in production already, so the new lands would be marginal. Worse, these lands would be put into production by further hacking down forests and destroying wildlife habitat and natural species. The deforestation and the tilling of the soil would both add further to atmospheric carbon, which in turn would cause increased global warming and unpredictable weather. This would put yet more pressure on agriculture. In a quest to eat, groundwater would be pumped for agriculture at an increasing rate, and

Deforestation in Thailand to open up new agricultural land.

Deforestation in Thailand to open up new agricultural land.

around the world groundwater would begin to disappear. (In some places in India today, the drop in groundwater levels, yearly, is already measured in meters.) And, as sea levels slowly rise due to rising global temperatures, millions upon millions of the world’s poorest people, in places like Bangledesh, will find flooding to be more common, making it ever harder to grow food. The entire system is interconnected, and failure in one area adds pressure to another, and can cause it to fail, which causes the next thing to fail, like dominos falling. We see this in power grid failures, we see it in financial market meltdowns, and we could see it with the environment. It could happen in various ways, but in all situations each failure would contribute to other failures. Continue reading