Rain Barrel!

I finally got around to setting up the rain barrel I bought last year. The wet season only lasts a couple more months, but hopefully I’ll be able to harvest some water to help keep my cherry tree watered during the dry months. In any case, I’ll tell this story with pictures, so… here we go!

Bits and pieces. Let’s hope I have everything!
Putting up the gutters. I intentionally hung them low so that snow would slide off without snagging them. I may eventually put rails on the roof to keep the snow there so that I can collect more water as it melts. I’ll need to assess whether the additional load on the roof will cause problems. I also set these up on the south side so that exposure to the sun willl hopefully keep things from freezing too badly.
Gutters and downspout all finished. Part way down the downspout is the RainReserve rain diverter. Instead of diverting everything, it captures water that falls along the interior sides of the downspout, while allowing bigger pieces of debris (like leaves) to fall through. Or so the theory goes…
Building a platform for the rain barrel, using the only flat surface within a half-mile radius.
Setting up the base. One side sits on cement blocks, while the other side sits on ice and rocks. It’s what we call MGEP (Mostly Good Enough, Probably) — the impeccable standard to which things are built on Serenity Valley. Actually, I’m not entirely confident it’ll support the weight of a full 300gal tank (2400lb). I guess we’ll find out!
Close-up of the rain diverter and tank hookup. The green hose is the overflow, which could also be hooked up to a second tank.

BootstrapSolar needs your support!

In my previous post, I mentioned that I was working on a solar power pack. I’ve since completed the prototype and tested it, so I’m almost ready for production. But in order to get there, I could use some help…

My solar power pack contains a 6000mAh LiPoly battery, big enough to recharge an iPhone four times over (or an iPad up to about 70%). It has two USB ports, of which one is configured to support Apple devices with output up to 1000mA (that’s equivalent to the iPhone’s AC adapter). The kit also comes with a 5W monocrystalline solar panel which can generate enough power to completely recharge an iPhone in two hours. Furthermore, the power packs can support up to 10W of solar panels for heavy users (or cloudy days). And it’s enclosed in a bamboo enclosure, which is a much more sustainable material than the plastics commonly used.

Basically, I built what I wanted for myself. It’s the kit I wish I had in Japan. It’s the kit I wish folks had in Japan in the days that followed the earthquake and tsunami when the power was out. I took this kit with me to Burning Man, and wished everybody had one.

Right now, I’m in the process of raising funds to pay for a small production run. The Kickstarter campaign that I started two days ago already has over $3000 in pledges, though I need $7500 for the campaign to finish successfully and to start production. If you’re interested in a kit, you can “reserve” one by pledging $90 or above, which is substantially less than what the final retail price will probably be (or how much you’d pay for a similar commercial product). Of course, even if you’re not interested in a kit for yourself, I’d appreciate any help getting the word out as well. Also, if this kit succeeds, it’ll give me the funds to work on other kits, so you’ll be supporting a larger project that aims to make solar technology available and accessible to more people. So, any support would be greatly appreciated, whether it’s a pledge on Kickstarter, or a simple “Like”.


Be Prepared

I’ve been obsessively following the latest news from the devastating earthquake that struck off the coast of Japan a few days ago, listening to internet streams of NHK radio, the public broadcasting service there, which has been covering the aftermath non-stop. My family in Tokyo were shaken but otherwise perfectly ok, though early reports of wounded literally blocks from my parents’ condo did have me somewhat concerned.

The M9.0 earthquake, possibly the 5th largest earthquake in recorded history, wreaked havoc across a wide swath of Japan’s north-eastern coast when it triggered massive tsunamis, some reportedly over 30ft high and reaching the 4th floor of buildings. This veritable wall of water traveled at speeds exceeding 20ft/second, and reached 10km (6 miles) in-land in places, sweeping away with it houses, cars, trains and people and pretty much anything not made of reinforced concrete. In addition to the sheer size of the waves, they also struck a mere 10 minutes after the initial quake (which itself lasted 5 minutes), leaving people with little time to evacuate in those affected areas. There are beaches where hundreds of bodies have washed up, and cities where over half the residents are unaccounted for. One prefecture alone is expecting a death toll in excess of 10,000.

However, help is on the way. One of the largest relief efforts, possibly in the history of the developed world, is converging on north-eastern Japan. Half a dozen countries, including New Zealand, Britain, Germany, France, Singapore, and China have rescue workers and medical teams en route. In addition to the 50,000 Japanese Self Defense Forces troops activated previously, another 50,000 were called up today for a total of 100,000 soldiers. Off the coast, an aircraft carrier, the USS Ronald Reagan, and a couple of destroyers of the US Navy have arrived to assist in rescue and relief operations, and I’ve read reports that the Marines may use amphibious landing vessels to deliver aid.

I think this particular disaster is worth following for those of us in the developed world, because there are already lessons we could learn. Japan is a wealthy and technologically advanced nation, and one which has spent considerable time, effort and resources in preparing for earthquakes. For instance, the high-rise condo my parents live in in Tokyo has elevators equipped with P-wave sensors that stop elevators at the nearest floor before the main quakes strike (P-waves travel at the speed of sound, and therefore move ahead of the actual earth-moving waves). Japan’s high speed rail service which travels at speeds exceeding 180mph are also similarly equipped, and suffered no casualties in this quake. Emergency broadcasts on TV can also warn viewers of incoming earthquakes, often before they actually can be felt. These are just a few examples of technologies available in Japan that I haven’t even seen in California — an equally quake-prone region.

Yet, as we watched the devastation spreading, it also became clear that there are limits to what technology can do. There are also limits to what the government can do. No doubt, this earthquake and the resulting tsunami was a hellish scenario that would’ve been difficult to prepare for or defend against. For many, escape simply was not an option. Sometimes, Nature wins.

But, as the country enters its 3rd night, a new kind of tragedy is unfolding. At one point, the radio announcer interviewed someone at an evacuation center, who painted a desperate picture: people huddled on rooftops with few blankets, no drinking water, no food, dwindling supply of medicine for the sick. The man ended with a desperate plea for supplies. From other reports, it seemed that many other isolated evacuation centers faced similar conditions. The suffering I heard about from survivors is a different kind of tragedy to the original disaster; one that might’ve been prevented, or at least eased significantly, with a little preparation.

If there’s one obvious lesson we could learn, it’s that the best preparation happens locally, starting with the individual on out. Every household should have a stockpile of food and water to last at least a week. In the event that evacuation is necessary, there should be a go-bag, equipped with essentials like food and water, emergency blankets, flashlights, a radio, spare batteries and cash. I’m hearing that flashlights are selling out in Tokyo, and if people don’t have flashlights, it seems even less likely that they have go-bags. Failing that (or to augment that), designated evacuation centers should be stocked with enough food, water, emergency blankets and other basic supplies to last at least a few days. While communication networks appear largely operational even in the worst hit areas, without power, people are unable to use their cell phones once their batteries run out (pay phones have become free, though long queues have been reported). This is a problem that could easily be solved by a few hundred dollars worth of solar panels mounted at each evacuation center, which could provide more than enough power to keep dozens of phones charged (or, at the individual level, a cheap $30 kit).

We’ve seen disaster victims suffer unnecessarily in a developed nation before, with Katrina. Even though the Superdome was designated as an evacuation center, it wasn’t stocked with necessary supplies. Prevailing emergency plans seem to be:

Step 1 – Get people to evacuation centers.
Step 2 – Wing it.

While I would not fault the Japanese government’s response by any means (which, if anything has been extraordinary, especially compared to FEMA during Katrina), the reality seems to be that Step 2 is challenging, even with the best of intentions. The reality is, getting supplies to masses after a catastrophic and unpredictable disaster is so much harder than prepositioning those same supplies when roads, airfields, and ports are accessible.

Better preparation can also save money, in addition to easing suffering of those affected. It costs a lot of money to activate troops and deploy helicopters. Supplies may simply cost more after disasters, since, after all, Econ 101 taught us that prices go up when demand goes up. It also may be harder to negotiate reasonable prices when desperate people are waiting.

Basic preparation such as those I outlined could also save lives. All day today, the radio reported of evacuees being air lifted from evacuation centers that lacked supplies to actually act as short-term emergency shelters. If those evacuation centers had been better stocked, those helicopters might’ve been better employed rescuing those who could really use help, like the 67 year old lady who clung to a tree for 15 hours after being swept away by a tsunami.

It is a pity that human nature seems to be deprived of foresight, and that it takes such tragedy to be reminded of our frailty. Even then, little may be done as a society, or even as a community. It is unlikely that we’ll be able to get politicians to increase funding for disaster preparedness, or that you could get stockpiles set up at the local shelter. But as individuals, we can learn and act. Tomorrow, it may be you and I, and what we do today could make all the difference. Be prepared.


A couple of days ago, I decided to hop over the fence separating my property from public lands to the west, to go walk to Lassen National Forest, which starts just half a mile down a forest service road. On the way, I planned on checking out a pond that’s located a couple hundred yards from the barbed wire fence. As I approached the fence, though, I heard a whisper. I undid my hood to uncover my ears. There was no mistaking the sound — the sound of trickling water!

I scrambled downhill towards the bottom of the ravine where I knew the sound must emanate from. The whisper turned into the full-on susurration of gushing water.

The seasonal stream was running!

Even though I’d always suspected the presence of a seasonal stream there, the sights and sounds stirred palpable excitement. Water! Gallons and gallons of water, gushing right through my property! The sudden appearance of this body of water made it seem that much more magical.

Though, in reality, the stream’s appearance could hardly be attributed to magic. In fact, the pond that I had been planning on visiting sits upstream from this creek, and is the very reason I suddenly started receiving water. The pond is actually the result of a large earthen berm that blocks that stream. When the water level rises high enough, the dam is flanked, releasing any additional water downstream towards my property.

The timing of its release is also unsurprising. It had snowed almost 2 feet over the past few weeks, but recent warm weather accompanied by rain had caused all that snow to suddenly start melting and rush downhill. When the pond filled up, the overflow started trickling through my property. Once all the snow is gone, probably in the next month or so, the stream will also stop running. But during that short window, snow melt from hundreds of acres of land will rush through that narrow gully on my land.

Exiting my property to the north, the creek eventually joins other tiny streams heading towards Pit River, which meanders west across the mountains to empty into Lake Shasta, to then continue south down the Sacramento River, eventually spilling into the Pacific Ocean where it would evaporate, condense into clouds that get blown back east, and fall as rain and snow on these same mountains to repeat the cycle.

On the way, some of it may be diverted to irrigate the rice fields and orchards in the Central Valley. So the next time you eat California-grown rice, or olives, or almonds, or perhaps fruits, you may be eating a tiny bit of that snow-melt I saw flowing through Serenity Valley.

Living here, I’ve gained a much deeper appreciation for water. Water is life. People talk about the “gold standard”, but I think there should be a “water standard.” Water is what makes life possible. No water, no life.

And until recently, I mostly thought of Serenity Valley as an inhospitably dry place. Indeed, from late Spring until mid-Autumn, there’s hardly any rain. In the summer, it’s typical for there to be zero precipitation for months. Last year, I had to haul water in to irrigate my tiny garden, and even that wasn’t enough.

But, lo! When I saw all that water gushing through my property, I felt like I’d struck gold. Nay, I felt like I’d struck life. If I can contain even a tiny fraction of the water, life can flourish on Serenity Valley. I can grow a much bigger garden, and even grow fruit trees. I can raise livestock. I may even be able to raise fish! It’s so dry here in the summer that things don’t even compost very well, but water changes that too. The soil isn’t great, but, as long as there’s water, I could build it up.

When I bought this land, I hadn’t really considered the possibility of homesteading here. Now that I’ve been contemplating that option, I was starting to doubt the suitability of this land for sustaining life. That changed the instant I heard that stream. Sure, there are much easier places to homestead, where growing seasons are longer, or summers aren’t so dry, or the soil is better. But with all that water, I think it’s at least theoretically possible to turn this land into a productive little farm. It wouldn’t be easy. It’d be an uphill battle all the way. But it just might be possible, and that’s pretty darn exciting.

As new possibilities blossomed in my imagination, I continued with my walk to Lassen National Forest as planned. I was tempted to spend more time around the new creek, but reasoned that it would still be running for at least a week or two.


The next day, having slept off my aquatic euphoria, I turned to more practical considerations. I started by walking the entire length of the creek, following it all the way through my property and out. The goal was to get an idea of the creek’s path, and to gain a better grasp of the terrain surrounding the stream. For the water to be usable during the dry season I would need to collect it, either with a dam of my own, or by diverting the water to a cistern. My hope was to spot potential sites for one or the other.

After entering my property from the west, a few hundred yards north of the south-west corner, the creek rushes down the steep ravine that I mentioned before, at a east-northeasterly orientation. The ravine eventually opens up to a bigger valley, the one I think of as actual Serenity Valley, which slopes gently down almost due north. The creek gradually wanders to the east, flowing out my property lines, then continues north parallel to my eastern border, eventually pooling in a flat area near the paved road, before disappearing into a large duct under the road just yards from the peg marking my north-eastern corner.

As I walked the length of the creek, it became obvious that damming a considerable quantity of water would quickly become a monstrous logistical and engineering feat, probably beyond my budget or skills. A more practical and practicable solution seemed to be to set up a small dam, maybe just a foot or two high in a natural bottleneck, to raise the water level just enough to make water collection easier. From there, some of the flow could be diverted by a series of pipes to a cistern located in a reasonably flat and clear area about 100-150 yards away. The terrain would allow the cistern to be located at a slightly lower elevation, and could be fed by gravity.

But, is there enough water?

As I observed the creek, I tried to make a rough estimate of its flow rate. To do so, I found a natural funnel where the stream was constrained between some large boulders, then imagined the jet of water being further narrowed, and pictured the water filling a gallon jug. It seemed like there was enough water flowing to fill a gallon jug in about a second. To be conservative, let’s call it half a gallon a second. That’s 30 gallons per minute, 1800 gallons per hour, or 43,200 gallons per day. If the creek were to run for 20 days, a total 864,000 gallons would flow through. (Incidentally, this method of approximation is called a Fermi estimate and is often employed by scientists and engineers to make ballpark estimates that often yield results in the right order of magnitude.)

So, even if I over-estimated or under-estimated by 100%, we’re looking at hundreds of thousands of gallons on the lower end, and well over a million on the high-end. It seems that diverting 10-20,000 gallons would hardly do any harm, yet would provide me with enough water to irrigate a large garden, raise a couple of heads of cattle, with maybe even enough left for a small fish pond.

But, would that be legal?

My natural inclination towards such questions would be to ask, “Does it harm anyone?” If not, who cares? After all, diverting 0.5-5% of a tiny seasonal creek seems pretty harmless. Being a seasonal creek that only exists for a few weeks a year, there’s no native fish or other wildlife I need to worry about. I’m not dumping toxins downstream. So, it seemed like it’d be something so harmless as to not even warrant regulation in the first place.

But then, this is California. And this is water we’re talking about. I decided to begrudgingly research the legal ramifications, half expecting to find that what I wanted to do would be bound tightly in red tape.

As it turns out, California laws regarding Water Rights apparently include an exception for crazy (or reasonable) people like me. On the FAQ page of the California Water Board’s website, I found the following:

There is one exception to the requirement that you have a water right. You do not need a water right if you take and use a small amount of water only for domestic purposes or use a small amount of water for commercial livestock watering purposes. However, you are required to register your use with the Division of Water Rights, notify the California Department of Fish and Game, and agree to follow conditions the Department of Fish and Game may set to protect fish and wildlife. The maximum use allowed under such a registration is 4,500 gallons per day for immediate use or 10 acre-feet per year for storage in a pond or reservoir.

Furthermore, “domestic use” is defined as:

… indoor household uses, watering of non-commercial stock used for the household, and irrigation of one-half acre or less of household land, such as a garden.

So, as it turns out, what I want to do is legal, and only requires registration. Though, the registration form asks for the estimated water usage in acre-feet, and since one acre-foot is 325,851 gallons, 10,000 gallons would be about 0.03 acre-feet, or a mere 0.3% of the 10 acre-feet that is allowed under this provision. To be honest, I feel like making a state worker (and someone from the DFG) process my registration for such a minuscule amount of water would cost the state of California more than it’s really worth…

One remaining open question is the cistern. My first thought was, of course, a DIY approach. A 10,000 gallon cistern could measure 15x15ft filled to a depth of 6ft (7.48 gallons fit in 1 cubic foot), and a 15x15x7ft box with 6″ walls would require about 41 yards of cement at a cost of probably $5000-7000 (though there’s also the question of how I’d get a cement truck out there). Even if reinforced with rebar, 6″ walls may not be sufficient, so that may be a low estimate. After doing some research, it seems above-ground plastic tanks may actually be more cost effective. They seem to be priced around $0.50/gallon (+shipping) or lower, and come in varying shapes and sizes so I could start with a small tank and add more. Being fully enclosed, evaporation wouldn’t be an issue either, and the bigger ones have man-holes for cleaning (the water is pretty murky, so I suspect there’ll be a fair amount of sedimentation).

Another related idea I had was to set up a micro-hydroelectric generator to run a pump, and lift the water to a higher elevation that way. About the only good that would do is to open up more possible locations for the cistern. But using the creek to generate power wouldn’t be practical for much else, since it probably only runs for a few weeks out of the year, and the creek is about 300 yards from my camp. Re-capturing energy when water is released from the cistern might be feasible, though it’s just as likely that water from the cistern would need to eventually be pumped higher since most likely locations for gardens are located higher up on my property.

All in all, preliminary indications are promising. If water-flow I’m seeing now is fairly typical, diverting about 10,000 gallons seems both legal and practicable. Tentatively, I may try to setup a small test this summer, and see how it does next spring. I could start with a cistern or tank in the 1000-2500 gallon range, and scale-up if that works out. As they say, Rome wasn’t built in a day, and if Serenity Valley is to see a transformation into Serenity Valley Farm –still a big if, mind you– it’s going to take years, if at all.

Solar Tracker Experiment

Several months ago, when I first posted about my manual two-axis solar tracker, a couple of readers asked whether a tracker really made that big of a difference. I had a theoretical answer based on simple trigonometry and the amount of light that falls on a surface relative to its orientation to the sun. Specifically, the amount of direct sunlight that falls on a square surface should be proportional to cosine(θ) x cosine(γ) where θ and γ are the angles between where the panel is pointed and where the sun is, in the x and y axes. By this theory, a panel that is perfectly aligned in one axis, but off by 30 degrees in the other axis would only get about 86.6% as much direct light. (This formula ignores ambient light, which in reality would clearly be present in addition to direct sunlight.) But I had no empirical data to back up my theory… until today.

On a sunny day like today, I’d re-orient my 100W solar panel 2 to 3 times in the course of the day. I usually point the panel to the east before going to bed so that it’ll catch the morning rays, and I’ll move it to point due-south later in the morning. In the afternoon, I might move it one or two times as well. The general idea is to keep the panel pointed to within about 20 degrees of the sun, since that should give me over 94% of available light at all times.

Today, when I went to re-orient the panel a little after 3pm, I decided to get a couple of actual readings. I first checked the voltage of the whole system (charge controllers hooked up to battery array), and got 13.3 Volts. I then measured the current between the charge controller and battery array, with the solar panel in the noon position, and also in its optimal position at the time, which is about 45 degrees from the noon position. With the panel in the “noon position”, I got 3.85Amps, or 51.2 Watts. I then moved it to the 3pm position, and got 5.55Amps, or 73.82 Watts.

The verdict, I might say, is that yes, the tracker makes a significant difference. If the panel had been fixed pointing due south, by 3pm I would only be getting less than 70% of the power that I could be getting, and that number would rapidly diminish as the sun continued moving away. This would also be the case in the morning, when I would get significantly less power than is available for the first few hours of sunlight. And, as it turns out, the numbers fit my theoretical model fairly closely, since according to my theory, my panel should be outputting 70.07% of its maximum when pointed 45 degrees away, while the actual numbers I got today were 69.37% (also, the angular difference was approximate, though, in theory, the sun should move by 45 degrees between noon and 3pm).

One thing to note, however, is that these results were obtained with my monocrystalline panel, which work best in direct sunlight. Thin-film panels, including amorhpous silicone panels, supposedly get more power from ambient light, so they may be less sensitive to orientation, though this is another hypothesis I’ll need to test with my 45Watt amorphous panels sometime.

Another question I got about the tracker was the effectiveness of the “manual” nature of the tracker. Wouldn’t an automatic tracker that constantly aligned the panel with the sun be more effective? Well, yes. But, to get 90% of available energy, the panel can be off by as much as 25 degrees in one axis (arccosine(0.9)). Or, at any given time, if I point the tracker 25 degrees ahead of where the sun actually is, the sun could move through a 50 degree arc and I would still be getting over 90% the whole time. Since it takes the sun over 3 hours to arc through 50 degrees, even manually moving a tracker every 3 hours will ensure that my panel gets 90-100% of available light at all times. So, an automatic tracker with all its complexity only gets maybe 5% more power than a manual tracker that’s re-oriented every 3 hours.

Food for a month

I’m down to my last few days before starting Project 31. I’ll be going on what will likely be my last supply run on Monday. I’d originally planned on “starting” Project 31 three days before the official Day Zero, so that I have a few days during which I could still leave if I think of anything missing. But, if current weather forecasts are accurate, I may be snowed in after Monday, so whatever I get on that run might end up being all I’ll have for a month.

Fortunately, I’ve got all my gear, so I’m down to just picking up a few odds and ends at the hardware store, then going on a big grocery trip to buy a month’s worth of food. This is easier said than done, as I’ve never planned a grocery list to last me a month. In fact, I don’t really even plan a week at a time, because I know I can go to town if I need more (though, generally, I buy enough fresh provisions to last me 5-7 days, and have weeks’ worth of non-perishables as backup).

The other limitation is that I’m not using my fridge/freezer, which means I need to buy food that won’t spoil in weeks of sub-freezing temperatures (which could be tough on vegetables), or above-freezing temperatures (which could limit the shelf-life of meats). Stocking up on non-perishable foods would be easy, but I don’t want to eat out of cans everyday, and having fresh food and diverse options is pretty important to me from a quality of life perspective. So part of the exercise is anticipating the kinds of foods I might crave, and to ensure I have the ingredients to cook them, and to make sure the ingredients last me as long into my stay as possible.

Obviously, there are trade-offs there. For example, in addition to fresh meat, which may not last longer than 2 weeks, I’ll have salted and cured meats that will last a month if kept cool (and I ignore “best before” dates). Instead of my favorite leafy vegetables, I might add root vegetables that have a better chance of surviving freezing temperatures without going bad. Instead of fresh milk, I’ll have canned milk and dry milk. And so on and so forth. There are some things that simply won’t last past the first week or two, and that’s ok too. At least if I can have, say, yogurt during week two, I’d only be without it for a couple of weeks thereafter. In some cases, it’s hard to guess what the shelf life would be (as advertised shelf lives are all super conservative), so finding out how long things actually last would be an interesting experiment in itself.

So, with all that said, here’s my list so far:

10lb bag of rice, 3 loaves of bread, 80-100 tortillas, one bag of bagels

Fresh Vegetables
4lb carrots, mushrooms, 2lb zucchini, kabocha squash, 5lb onions, 5-10lb potatoes, 3 bags mixed “southern greens”, 2 heads garlic, fresh ginger, 2 heads of cabbage, 3 bags brussel sprouts, 3lb beets, 2 tomatoes, 3 avocados, 4 bell peppers, cauliflower

3-5lb pork, 1-2lb chicken, 1-2lb ground turkey, 2lb sausage, 2lb sandwich meats, 3lb salted pork or bacon, 6 cans of fish, 3 pouches of chicken meat, 36 eggs

2 boxes dry milk, 4lb cheese, tub of yogurt, cream cheese, 2lb butter (salted & unsalted)

Dry goods, non-perishables, misc
canned soup, canned chili, ready-to-eat indian food, chef boyardee, canned coconut milk, energy bars, chocolate, peanut butter, jam, honey, maple syrup, flour, sugar, baking soda & powder, yeast, dried fruits, nuts

I’m sure I’ll add more when I’m at the grocery store, so this is kind of a baseline. Ultimately, I’m also not terribly worried because this is mostly a quality of life problem, not one of survival. I’ll have plenty of calories to survive off of — it’s mostly a question of whether I’ll have a high enough quality diet to be reasonably content. I also realize that no list will ever be complete, and that by day 15 or 20, there will be something I’d want that I simply don’t have. And that’s okay too, because the whole point of Project 31 is to discover the things I’m missing. In fact, I’d be pretty happy if by day 15 or 20 what I’m missing most is sushi, and not something actually more critical.

LED Light Bulbs, the numbers

I recently picked up a couple of LED light bulbs that are starting to become more popular in Japan. After comparing a few different options from various major manufacturers, I settled on the “40 Watt” (450 lumen) bulbs made by Panasonic. The main draws for me were the relatively high efficiency (more lumens per watt) compared to other LED bulbs, and the fact that they emit a warmer orange color rather than the harsh bluish light typical in CFLs. Another draw was the fact that these bulbs are rated to last 40000 hours, or about 5x as long as CFL bulbs, which could reduce waste.

On the other hand, at around $30 a pop (2380JPY, to be exact), they’re pretty expensive as far as light bulbs go. Are they worth it? I decided to run some numbers, comparing the LED bulb I got to a traditional incandescent 40w light bulb, as well as “40W”, “60W” and “100W” CFL bulbs. The results are in this spreadsheet below (see the original document on Google Docs).


  • klmh – “klmh” stands for “kilo lumen hours”, and can be thought of as the total amount of light emitted, if it were possible to gather light over time and put it in a box. One klmh equals the amount of light emitted by a 1000 lumen lamp over 1 hour, or a 1 lumen lamp over 1000 hours. Technically, a lux is a better unit with which to measure total light emission, but that information wasn’t available (while lumens were) so I used Kilo-Lumen-Hours to compare bulbs of different brightnesses.
  • Power costs – I used $0.15 per kWh. Actual energy costs vary from around $0.10 to $0.20 in the US. See prices for September 2010. Calculating the cost of energy for off-grid systems is much, much harder, and would vary widely from system to system, so that is left as an exercise for another day.
  • Annual usage – To calculate “costs over 5 years”, I assumed an average 5 hours of usage per day, or 9125 total hours of usage.
  • Total costs – The “total cost” calculations combine the amortized cost of the bulb with estimated energy costs (again, at $0.15/kWh).

I tried to compare the bulbs from a wide range of perspectives, and ended up with all sorts of numbers. I’ve highlighted the ones that I think are relatively informative, but, as you can see, some bulbs do better in some comparisons, and do worse in others. In other words, there’s no clear all-around winner.

Efficiency – In terms of efficiency, the “40W” LED bulb (65.22lm/W) was bested only by the “100W” CFL bulb (67.33lm/W). In reality, the LED might perform a little worse, because LED lamps have more directed lighting patterns, so despite what the lumen rating is, the actual total amount emitted may be less than CFL bulbs. As a side note, it was also interesting to see that the efficiency of CFL bulbs improved with increase in wattage. I think this is because fluorescent lights become more efficient the longer they are, and higher wattage CFLs simply have longer tubes.

Cost – If all you care about is having a light bulb –any light bulb regardless of brightness– in a socket, LED is by far the cheapest option. Even though the upfront cost of the bulb is considerably higher than the alternatives, the additional expense is offset by the bulb’s long lifespan and low energy usage.

On the other hand, LED bulbs are relatively dim compared to the brightest CFLs, and if you must have lots of light, CFLs are cheaper for the amount of light you get. This last point is important. Even though a 26W CFL bulb has 1/10 the cost of a 6.9W LED for the same amount of light, the simple fact that it uses more than 3.5 times as much electricity can not be overcome. Having a 26W (“100W”) CFL in that socket will cost you more than twice as much as using a 6.9W (“40W”) LED bulb. But if you must have that much light, it is cheaper to use one “100W” CFL bulb than to use multiple “40W” LED bulbs.

More is more, less is less
Retailers often try to get consumers to buy more stuff by offering lower per-unit costs when purchased in bulk. While buying in bulk may lead to real savings, such deals can also be a pitfall that leads to excessive consumption and spending. The question to ask is, “Do I have to alter my behavior, in order to take advantage of this deal?” If the answer is “yes”, it is best to stay away from bulk purchases. For example, let’s say a grocery store has a deal on ice cream, such that if you buy 2, you get 1 free. The question is “Would I eat more ice cream if I bought 3?” If the answer is “yes” (and let’s be honest now), just buy one, because one is still cheaper than two, in absolute terms. On the other hand, if you’re dealing with something like toilet paper where abundance probably won’t lead to higher consumption, buying in bulk might actually save you money.

The same applies for lighting. If you can get away with less lighting, it will save power and money. Don’t let the illusion of better “value” trick you into consuming more unless that is really what you want, because you will pay more for it. Using one “100W” CFL bulb for 5 hours a day over 5 years will cost an estimated $38.18, while a “40W” LED bulb used for the same duration will only cost $16.29, even when factoring in the cost of the bulbs. Yes, you get less lighting, but you get less for less, while more costs more.

Lighting accounts for 12% of domestic electricity consumption in the US, and I would argue that that makes it a ripe target for reduction. While current trends are towards improving efficiency, Jevon’s paradox warns us that efficiency may in fact increase consumption. If that is true, it seems to me that the true path to reduction is, well, to reduce. That is, rather than merely swapping 60W incandescent bulbs with “60W” CFL bulbs, consider using “40W” bulbs. Instead of having area lighting consisting of 5 or 6 bulbs, consider having 5 or 6 individual lamps located strategically, so that only localized areas that actually need lighting are lit at any given time. Or, for that matter, turn those lights off entirely, and go to bed early. Artificial lighting can interrupt our natural circadian rhythm, leading to sleeping disorders and other maladies. So going to bed early and getting some extra sleep can save your health and the planet. Now that’s what I call a good deal.