More on Virtual Daylighting

I posted earlier about an experiment with virtual daylighting on a small scale using indirect light.

Here is a post about a direct experiment where the designer replicates the sky, clouds and all, using arrays of LEDs.

Probably not an energy efficient use of LEDs but an interesting experiment that requires some thought about the trade-offs between energy efficiency and productivity gains.

ESLs - Comparison to other lighting technologies

In a previous post I compared several light sources to understand why a person might choose one over the other.

I bumped into this story on treehugger about Electron Stimulated Luminescence (ESL) bulbs. These lights use an approach like a CRT television to cause a phosphor to light up.



Technical specs for the bulbs are:

• efficacy = 30.7 lm/W
• lifetime = 10,000 hrs
• CRI = 85
• Color Temp = 2700K, 2900K, 4000K

Other points which the makers heavily emphasize:

• Fully linear dimming with household dimmers (vs CFLs)
• Mercury-free, environmentally-friendly materials throughout (vs CFLs)
• Mount in any orientation [heat issues] (vs CFLs and probably LEDs)
• Instant on at full brightness (vs CFLs)
• Lasts approximately 3-6 times longer than an ordinary incandescent bulb

They don't post a price but do say about price: "it will be price competitive against LED products."
If I take "price competitive" to mean 25% less than an equivalent LED bulb, that leads to an expensive bulb... (~$136/klm ESL vs $5/klm CFL).

Plotting that information in the same charts I used earlier gives the following:

The ESL bulb falls into a pretty good space in terms of visual quality. However, its efficacy is quite low compared to the other choices in the space.

Assuming that the FAQ comparison with LED lighting is any indication of how they intend to price the bulbs, then a more serious problem emerges.

The price | performance ratio is quite poor for the ESL. Its lifetime and efficacy values are FAR too low to be priced anything like an LED light. To be competitive, the price would have to be closer to that of a CFL (1/30th the current estimate).
Being Hg free, made from environmental friendly materials, dimmable, providing instant on and lacking heat issues are all very nice but, given it is only about 1/3 as energy efficient as a CFL, a 30x price premium is not warranted ... it would be hard to justify a 2x price premium I suspect.

So unless the pricing comparison with LEDs is highly misleading, ESL is likey to be DOA.
Mass market will buy CFLs because of price | performance.
Specialty applications focused on "green" creds will use LEDs because they are far superior in those aspects.

More Energy Efficiency and Leverage - It's STILL not about caulking.

I can't make a good decision about how to make my energy usage sustainable unless I know which activities are using the most energy. The chart presented here attempts to give an idea of the scales of energy I've been talking about in previous blog posts.

The total energy usage in the US per year (as noted in this blog post) is ~1x10^20J. For comparison, that is:

• ~1.8 million times the energy released by the atomic bomb dropped on Hiroshima and  
• ~2600 times the energy that the largest atomic weapon in the US arsenal would release if detonated.
• ~ 47 times the energy released by all nuclear tests conducted... ever...

Closer to home, the total electricity used per year by the average US household is about 4x10^10J. While media focus has been on making our homes more energy efficient as a good way to tackle sustainability, it turns out that driving a single car each year uses ~5x more energy than our homes consume*.
Increasing fuel efficiency or reducing miles driven by 20% would be the equivalent of reducing your home electricity usage by 100%. That's big leverage. Better than caulk or fluorescent light bulbs.

Flying is also pretty energy intensive. A single flight from SanFrancisco to Tokyo uses about the same energy as driving a car for a year** or ~3.5x the average annual electricity usage of a home. With about 4 flights per day 365 days/yr that is ~5100x the average annual electricity usage of a home per year of flights... and that's just one destination from one airport...

So shooting for 30% reductions in energy usage in the home may not be entirely where the leverage lies.

*assuming 15,000 mi/yr @ CAFE standard 27.5 mpg.
** assuming 5148 miles @ 5.29 mpg of kerosene.

Energy Efficiency and Leverage - It's not about caulking and insulation.

Lawrence Livermore National Labs published a very interesting diagram of energy usage in the US for 2009 (above picture).
One thing to take away from it is that most of the inefficiencies ("rejected energy") come from:

• transportation (37%)
• losses during electricity generation (48%)

Combined commercial and residential losses amount to about only 7%.
So even if I could make all commercial buildings and houses 30% more efficient through energy efficiency retrofits, new appliances, smart monitoring, lighting and HVAC feedback controls, etc, that would only reduce the rejected energy by 2%.

Leverage comes from addressing transportation and energy generation and transmission.

• Electric Cars:
• LLNL assumes 25% efficiency for conversion of petroleum energy to useful transportation energy. If you assume that electrifying all transportation could improve this to 90%, that would reduce rejected energy by 24%. That's 12x the impact of green building on energy usage.
• Distributed Generation: Solar panels and wind in your backyard.
• Transmission losses are estimated at about 6.5% for 2007. If those losses were eliminated (optimistically) by putting solar panels and wind farms near the consumers, that would reduce rejected energy by ~1.5%, or slightly less than making all buildings "green" with respect to their energy usage.
• A much bigger deal is the reduction in fossil fuel usage this would allow. Assuming that wind, hydro, geothermal, nuclear and solar are 100% "efficient"(no rejected energy), that means fossil fuels are only about 24% efficient. If you could replace all the coal with some combination of these other sources (preferably wind or solar to allow for distributed generation), that would reduce rejected energy by ~25%. That's 12x the impact of green building (albeit at potentially high cost).

This is not to say that green building is unimportant but, if this analysis is correct (or even in the ballpark), then it's far less important in the big picture of energy efficiency than I thought.
It is important to concede that the changing all transportation to electric drive and replacing all coal with solar or wind is a HUGE hurdle to overcome. Making buildings greener may not be the longest lever but it's one that is easier to deal with.

A better way for electric cars? A Better Place.

What are the two main things you worry about with electric cars?

1. Price
2. Range

Gasoline is great because it is a well established, subsidized fuel with very high energy density (1.3x10^8 J//kg). That makes it easy to carry around and get pretty far with. Plus, when you run out, there's always a gas station somewhere nearby. Price and range... not a problem.

Electric cars are limited by their batteries. Li-Ion battery's energy density is nowhere near as high as gasoline (5.2x10^5 - 7.2x10^5 J/kg - gasoline has >180 times more energy per kg of "fuel"). Even accepting that a gasoline engine is 30% efficient vs a 90% efficient electric motor (i.e. total energy that would be converted to work per kg of fuel is 3.9x10^7 J/kg for gasoline vs 6.5x10^5 J/kg for Li-ion), that yields ~60 times more energy per kg of "fuel" from gasoline than from batteries. So to get the same range as a gasoline car (from one tank of fuel), requires either:

1. A very large battery -or-
• If a typical car holds 15 gal of gasoline (@ ~2.7kg/gal = 40.5 kg) , a battery that contains the same effective energy would need to weigh ~2430kg ... where a Honda Civic weighs about 1270 kg... not practical to carry or to pay for.
2. The ability to "refuel" the battery in less time than refueling a car 
•  Even with the best recharger possible, it takes hours (~4 hrs for a Tesla roadster) vs maybe 5 minutes to refill a gas tank.
• With a 100 mile range per battery charge, that would require about 4 battery charges per tank of gas (assuming CAFE standard of 27.5 mpg and 15 gal tank = 412 mile range). Sixteen hours (battery) vs 5 minutes (gasoline) (assuming both cars start empty).

 Those are pretty bad starting places to catch up from.

So Shai Agassi has an idea: Treat the electric car like a cell phone.
The customer buys miles and gets a subsidized car. The batteries are the medium for the "minutes." You never own them, you just use them.
Which means you can now swap batteries because you don't care about the specific battery that you have, only that you're getting the mileage you're paying for.
Suddenly the range problem goes away (~1min to change the battery).
Suddenly the price has a means of being subsidized (ala cell phone contracts that keep the price of the phone low for the end user).

Kind of like Blue Rhino propane tanks ... but way cooler.

And he created a company Better Place to do it:

• Get the cars built
• Get the battery swap system figured out
• Get the infrastructure in place
• Prove to the world that it can work

Check out this video (or the video below) of the system working in Tokyo. It's real.


So, admittedly, it only works where you have the infrastructure, but it certainly gives a new direction for addressing the two big problems of EVs.

Biking to work and energy efficiency

Bike to work and stop global warming.
Bike to work and get healthy.
Ok. Since it's so good for me and my planet and I'm only about 6 miles from work, I finally decided that I should give this a try.

I used a cool iPhone app (Runkeeper) to log how far I went and how fast I went there. As part of the app I got an estimated calorie usage... and that got me thinking about energy efficiency:

• I burn about 240 calories one way on this trip (~6 miles).
• That is about 1x10^6 Joules (~1 MJ) of energy.
• One gallon of gasoline has about 1.3x10^8 J of energy in it (130 MJ).
• My Prius, on roughly this same route, gets around 42 mpg (I'm a terrible hypermiler). So it takes around 0.14 gal of gas to make the trip, or1.8x10^7 J (~18.6 MJ).

So my bicycle commute is more than 18 times more energy efficient than driving.
...And I drive a Prius.
If you use the CAFE Standard fuel efficiency for a passenger car in 2010 (27.5 mpg), then that bicycle commute is more than 28 times more energy efficient than driving.

To be as energy efficient as cycling, the car would need to use 0.01gal of gas for the 6 mile trip, which is 600 mpg! Whereas the current automotive X-Prize is only looking for 100 mpg... 6x short of what is needed.

So we REALLY need to be doing more of what Copenhagen is doing with making cycling mainstream:

"If you make the bicycle the fastest way to get around the city ... you're going to get everyone and their dog to do it."

• Pervasive use of dedicated bicycle lanes.
• 37% of all people commuting to work or school use bicycles.
• 50% of all trips in the city are made by bicycle.
• Double bike lanes to accommodate bike traffic volume in some places.
• "Green wave" timed to give cyclists a no-stoplight flow into the center of the city for 6km (3.7mi).
• Red LED lights on the bicycle lane demarcation that sense coming bicycles and flash to warn cars to avoid right turn conflicts.
• Dedicated parking spots for cargo bikes (taking away 1 car parking spot for 4 cargo bike spots).

Picture credit: Adam Stein (terapass blog)

The essence of a drinking cup

How would you rebuild a disposable drinking cup if you had sustainability in mind?

• minimum material per cup
• use of renewable resources
• use of recyclable materials
• low cost
• small storage and transportation foot print
• high packing density (less restocking labor costs)

It might look a lot like this:

A paper cup from Taiwan.

Opened to hold water. You would hold this and drink from it.

This is the dispenser next to the water cooler. That is a HUGE number of cups (100s) in a tiny space. 

Compare to the ~15 styrofoam cups in this picture stacked to roughly the same height as the paper cup dispenser box.

This won't work for hot drinks and it's difficult to use a single cup for more than a few drinks, but for it's intended purpose: getting a quick drink of water, it's quite effective.

It would be better to not use disposable cups at all but...

stacked Styrofoam cups photo credit: Dan Meyer @ http://blog.mrmeyer.com/?p=69

EDF Climate Corps Handbook

The Environmental Defense Fund (EDF) has published a free guide to making your office building more efficient system by system. It has:

• An overview of how to approach the problem (7 steps)
• Estimate baseline energy use intensity.
• Commission an energy audit.
• Consider interactions between systems.
• Perform financial analysis of possible efficiency investments.
• Prioritize options for investment.
• Evaluate financing options.
• Post-implementation follow up.
• Tips for identifying and overcoming common barriers to implementing energy efficiency
• Structural
• Split incentives - one who bears cost of improvements does not accrue benefits
• short lease terms - payback period is longer than least term
• Organizational
• Scarce resources
• “Language barriers” between finance and facilities
• Coordination challenges across finance, human resources and facilities
• Limited accountability for green initiatives
• Financial
• Payback period expectations are unrealistically short
• Large up-front costs to implement some improvements
• lack of awareness of  tax incentives or utility subsidies
• Simple, practical suggestions for which systems to look at first (lowest cost for highest impact)
• Which systems exist and which you should go after first
• Lighting
• HVAC
• Office equipment
• Water heaters
• Building Automation Systems  / Energy Management Systems
• Data centers
• Fleet vehicles
• Which areas to focus on and which to skip within each system
• Behavioral and policy changes
• Retrofits
• Equipment replacement
• Tips on prioritizing which improvements to make
• Key questions to ask and information to gather around each system

• Case studies to help justify implementing changes in any particular area.

e.g. Financial case study: Until 2001, the 1.4-million-square-foot Hewlett Packard (HP) campus in Roseville, California, was operating an EMS with limited automation, which required labor-intensive manual adjustment of controls in order to curtail energy loads during peak demand events. Using funds available from the California Energy Commission and the local municipal utility (Roseville Electric), HP upgraded its EMS and added additional sensor and control points for ventilation and lighting systems. The changes gave HP the capability to shed 1.5 MW of its 10.9 MW peak demand without disrupting occupants. HP now uses the EMS load-shedding capabilities on a day-to-day basis, saving $1.5 million annually in energy costs as a result. The EMS upgrade cost $275,000, but incentives covered $212,000 of the project cost, giving HP a payback of less than one month on the project.⁶

• Ideas for presenting financial and non-financial arguments to the appropriate stakeholders in the organization.
• High level primers and key-word dictionaries on main building systems and links to more information about them to help focus one's learning.

The EDF also has a program where companies can host a Climate Corps member (MBA student) and have that student come on site for ~10 weeks to implement an energy efficiency program based on the guidelines in this handbook.

A very interesting package for kick-starting energy efficiency at your company.

The Intersection of Cats, Video Games and Conservation

Why is it so difficult to train cats to stop doing something?
As predators, they evolved to deal well with intermittent reinforcement : 9 out of 10 times, it won't catch the mouse, but the 1 time it does is enough to keep it hunting for another day. It it quit every time the mouse escaped it wouldn't be a very good predator.

What do we love about the really addictive video games?

• Just one more turn before I eat lunch (Civ 2)
• I can get one more turn if I eat ancient unspeakable fruitcake (Kingdom of Loathing (KoL)).
• So-and-so has found a lost baby horse, can you give it a home? (Farmville)
• Is that all you got? (Modern Warfare 2) 
• Raining on their Parade and a whole host of other contrived achievements (Team Fortress 2)

More intermittent rewards for making progress against some goal, spaced just right in time to maintain a sense of progress and recorded for ourselves and others to see how much progress we've made.

Why is conserving resources so hard?
Our predator nature loves intermittent reinforcement but conserving resources is, generally, a slow cumulative, silent process.

• There are no achievements, trophies or (annoying) progress messages to your friends.
• No normalizing scoreboard that tells you how well you're doing against "the best" or against "100%."
• No updates, patches, new weapons, armor, new recipes or new quests. No $5 DLC packs.
• Replay value is pretty bad. In fact, the first game never ends.

Why would I play *THAT* game?

Whoever can turn conservation and efficiency into a game, a really good, addictive game, will win for all of us.

Lighting Labels coming in 2011

Better information for comparing light bulbs is coming next year.

Read this this earlier post to understand what these terms mean.

• Brightness = Luminous flux
• Brightness / Energy Used = Efficacy
• Light appearance = Color Temperature

Comparing Light Sources - LEDs vs Fluorescents vs Metal Halide HID

From the previous post, one could conclude that LEDs, Fluorescents and Metal Halide HIDs were all pretty much the same: High efficacy, OK to good CRI and good color temperatures.

Yet what we see are fluorescent bulbs everywhere.

One way to compare these light sources is by bulb life vs cost per lumen output with efficacy taken into account. That looks like this: "Good" is high and to the left with a larger bubble.

One conclusion that immediately stands out is how expensive LED lights are relative to the alternatives. They may be 2x as efficient and last 5x as long, but they are ~38x - 175x the price. That makes adoption of LEDs very difficult for most applications that don't have some other needs specifically met by LEDs.

Some of those special needs:

• LEED certification 
• LED lighting is more efficient so it can be used towards energy efficiency credits (EAc1). If 25% of a commercial building's electricity usage goes towards lighting and you can cut that by 50%, that's a 12.5% reduction in electricity cost.
• LED lighting is more easily controlled (dimmable) to allow for controllability of systems - lighting (EQ6.1).
• Flicker
•  For some tasks and working conditions, 60Hz cycling from fluorescents can cause eye strain, especially if it is used with other visual equipment that runs off 60Hz AC. LED lighting has a 120Hz cycling which means it is much more difficult to detect flicker and it is less likely to beat with other equipment running at 60Hz.
• Dimming
•  Commercial use fluorescent bulbs (T8, T10 and T12) are not easily dimmable due to the construction of the ballast that keeps them lit. LEDs are dimmable using standard dimming equipment. This is important for applications where light level control is desired.
• Directionality
•  LEDs are point sources that can be configured more easily to provide a variety of lighting patterns (focused to diffuse) while fluorescent bulbs are generally quite long making it more difficult to use as task lighting or for other special lighting purposes.
• Toxic waste disposal concerns
• Fluorescent bulbs contain mercury which is a hazardous substance. LEDs do not contain mercury, though they are still eWaste and need special handling for disposal.

• Low temperature operation
• LED lighting performs better at lower temperatures. In fact, life time if greatly reduced if they operate at too high temperatures (hence all the heat sinks on the LED bulbs). This makes LED lighting a natural fit for lighting refrigerated displays.

• Green image
• The current perception of LED lighting is that it is the next big thing in energy efficiency and is, therefore, green. Using this perception to advertise your greenness is good marketing.

While Metal Halide HID compares well on the cost/lm vs lifetime graph, it does have a major strike against it, besides the borderline CRI: restrike time. This is the time it takes for the bulb's arc tube to cool sufficiently to restart the plasma. This can be several (1 - 15) minutes. A long restrike time makes such bulbs very difficult to use in locations where individual light control is required (e.g. office spaces or residential). Using fast starting HIDs greatly shortens the life of the bulb.

So as the cost of LEDs drop (cost comes in line with alternatives), energy costs rise (efficacy difference becomes more important) and green building codes become more prevalent (raising the minimum energy efficiency requirements for new buildings), the ROI of LED lighting will rise vs fluorescents until LED lighting makes economic sense. 

It's just not quite there today.

Comparing Light Sources

One of the low hanging fruit in energy efficiency is replacing incandescent lights with fluorescent ones.

OK.

Then there is much news about how big LED lighting, outside of TV and LCD monitor back-lighting, will be:

"LEDs will account for almost half of a $4.4 billion market for lamps in the commercial, industrial and outdoor stationary sectors by 2020."

So LED lighting is where it's at.

OK.

So which is it and why?

First some terms:

How lighting is measured:

• Photometry: The science of radiated energy as observed by the human eye. Metrics of photometry incorporate wavelength and sensitivity of the human eye at various wavelengths (luminosity function).
• vs Radiometry, which is the science of radiated energy without regard to human perception of the radiated energy.
• Luminous Intensity: measured in Candela (cd). Defined as:
• The luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency 540 × 10¹² hertz (~550 nm) and that has a radiant intensity in that direction of ¹⁄₆₈₃ watt per steradian
• Luminous Flux: measured in Lumens (lm). The light produced by a light source that emits one candela of luminous intensity over a solid angle of one steradian. Light bulbs usually label the output of the bulb in Lumens somewhere on the package.
• Illuminance: measured in Lux (lx) or Foot Candles (fc). The total luminous flux incident on a surface, per unit area.
• For metric units: Lux = lm/m^2
• For English units: Foot Candles = lm/ft^2

How light sources are characterized:

• Efficacy: The amount of illuminance generated per watt of energy input.
• Color Temperature (CT) / Correlated Color Temperature (CCT): The "whiteness" of light generated from a source. Correlated to the color of light produced by a radiating black body of that temperature (K).

• Color Rendering Index (CRI): The ability of a light source to correctly reflect accurate colors in the environment. CRI = 100 is perfect reproduction. CRIs in the range of 75-100 are considered excellent, while 65-75 are good. The range of 55-65 is fair, and 0-55 is poor.

I plotted the source characteristics for some common light sources below to show how they relate to each other. "Good" translates to high, to the right(ish) and with a large sized bubble.

What does that mean?

• Incandescent and halogen bulbs are what most homes use today so they are the baseline against which all other lighting is most easily compared. 
• It has good CRI, medium-low CT and very low efficacy. 
• i.e. objects appear to be the "right" color when illuminated and the light itself is "warm (reddish)" but takes significant energy to produce very much of.
• Fluorescent lights are very common, particularly in commercial lighting and are the other light source which you've probably encountered frequently. There is large variation in the characteristics available depending on phosphors used but:
• Newer bulb types have reasonably good CRI, a wide range of CCTs (med - high) and high efficacy.
• i.e. objects appear to be nearly the right color, light can be anywhere from "warm" to "cool (white)" (depending on the bulb) and energy is efficiently converted to light (~5x incandescent).
• Metal Halide High Intensity Discharge (HID) are more common as outdoor lighting (and a variant - Xenon HID in car headlights).
• It has borderline good CRI, medium CT and high efficacy. 
• i.e. objects appear to be the "almost right" color when illuminated, the light itself is "cool (white)" and energy is efficiently converted to light (~7x incandescent).
• Low Pressure Sodium lighting is the the yellow street lamp you've probably seen in the parking lot that made it impossible to figure out which car was yours because they all looked grey.
• It's very good at converting energy to light, but it's not light you want to look at... unless you are an astronomer and want to filter out the city of San Jose's light pollution from your observations...
• LED lighting is still fairly rare but is starting to show up in some more efficient building designs,  vending machines and refrigerated display cases.
• Newer LED types have reasonably good CRI, a wide range of CCTs (med - high) and high efficacy.
• i.e. objects appear to be nearly the right color, light can be anywhere from "warm" to "cool (white)" (depending on the phosphor used) and energy is efficiently converted to light (~10x incandescent).

Conclusion: modern fluorescents are quite good from a light quality standpoint, modern LEDs are similar as are (some) HID lamps. LEDs are clearly more "efficient" but adoption is still low. From this basic data one would expect that HID penetration would be higher too. Why is it not?

I'll get into more characteristics of these light sources later to better understand why the lighting situation looks like it does today, but hopefully this post went a good way towards explaining why the forerunners are what they are.

At least this proposed light bulb label should now makes sense:

Interesting Mixed Metaphor - BP Oil Spill and Energy Efficiency

This story from Treehugger highlights an interesting quantification of the BP Oil Spill in terms of energy being wasted.

• The estimated cost to clean up the oil spill ($40 B) is many times greater than the cost to retrofit 75,000 houses ($1 B) and save the energy equivalent of the gulf oil spill every year.
• 75,000 houses = mid-sized U.S. city or large suburb of a major city, like Chattanooga, Tenn. or Providence, R.I.
• A typical home energy retrofit costs around $10,000 per house -- before any utility or governments energy rebates are applied.  

Of course, wasted energy is only a small part of the problem. There is the matter of millions of barrels (>114 million gallons = ~2.7 million barrels in worst case estimate or ~30M gal for a more conservative estimate) of crude oil in the water:

• Oil washing up in coastal habitats killing animals, destroying ecosystems and heading towards Florida and the Atlantic Ocean.
• Tons (>1.2 Million gal) of toxic chemicals being sprayed on it (dispersants) with unknown long term impact
• The effect of the dispersed oil droplets sinking in the water column impacting sub-surface life.
• Tons of methane, >20x more potent than CO2 as a green house gas, that have been released (around 2900 cu ft of methane per barrel of oil = 7.8 billion cu ft = ~112,000 metric tons = ~ equivalent to green house gas effect of emissions from 20,400 cars)
• Increased hyopxic "dead zone" in the gulf (between 8% and 30% larger than normal) possibly from all the methane being pumped into the water along with the oil, further impacting the ecosystem.
• The short and long term cost of health effects from the oil, chemical and gas exposure on clean up volunteers.
• The resulting economic and job loss throughout the market chain as people cannot catch fish, sell fish, buy fish, so fishermen can't buy things thereby hurting local businesses which rely on the fishermen's income. (1% of Lousiana's economic output according to NPR)
• More economic loss from the moratorium on deep water drilling (16% of the economic activity of Louisiana according to NPR).
• The loss in stock value of BP impacting the retirement income and viability of retirement portfolios for large numbers of people, bringing further economic hardship on people already in the middle of one of the worst recessions in recent history.

So interesting comparison: yes... but sort of missing the big picture.

Necessity is a *Mother* ... oh... of invention

This is a short video of how one architect has used very limited space (344 sq. ft) to maximum effect (24 purposes built into that single space) in a city (Hong Kong) where space is at a premium.





I'm not saying this is how we should all strive to live or even how we'll end up living despite our ambitions, however, it does get one to thinking about what we'd do differently if we were faced with scarcity of this sort on more of our design problems.

• Not enough space to have 3000 sq ft. per home.
• Not enough fuel to drive 30 miles to work and back. To drive 10 miles for groceries. To ship groceries 1000s of miles to a supermarket.
• Not enough water to "waste" it on grass or even on washing clothes.
• Not enough chemical or electrical power to level mountains or keep our homes and workspace air conditioned or heated. Or lit for more than a few hours a day artificially.

I'm not a Luddite, but it seems like thinking as if we had these restrictions might actually result in some greener, more sustainable approaches.

What (Other) Kind of Business Could I Build Around Energy Dashboards?

In my last post, I came up with a bad model for an energy dashboard business based on annuities paid by the utilities companies for energy saved. However, there did seem to be a bright spot for selling the dashboards to the utilities to install themselves. Looking at that a little more closely...

According to the US Energy Information Administration, CA electric utilities generated ~11.1M metric tons of CO2 in 2008. The three year average (2006-2008) was ~10.2M metric tons.
Using the same number of customers in CA and 10% savings factor as assumed before, implementing energy dashboards would save ~ 1.1M tons of CO2. Spread across the ~12.9M customers in CA at the current price for carbon (~$19/ton CO2e), that is about $1.68/customer.

If you add that to the ~$35.6/customer savings in direct generation costs, that is ~$37/customer*yr.
So if a utility is willing to accept a 3 year pay back period, then each installation could cost up to ~$111, for a TAM of around $1.4B for serving all of CA.
Not too bad as long as you have an alternative revenue stream planned for after the initial sale (e.g. s/w license fees for maintaining the dashboard customer feedback, data aggregation, reporting, etc).

The utilities' ROI increases the more effective the actual energy savings and the less expensive the installation. So to compete here you'd need to prove that your system will create and maintain better energy reduction outcomes per $ of installed equipment. If you could do it all in s/w leveraging customer's existing h/w or without any installed h/w, that would be the best.

What Kind of Business Could I Build Around Energy Dashboards?

In a previous post, I wrote a bit about why so many smart grid cleantech companies were focusing their efforts on utilities instead of consumers: the power of big numbers leverages small efficiencies into large $ amounts.

With that knowledge, what kind of business could I build around selling energy dashboards to the utilities?

A few assumptions, some of which are probably pretty optimistic just to simplify things without really changing the conclusion (I hope):

• I want to run a business based on annuities (utilities pay me a "subscription") rather than hardware and s/w services (utilities buy my h/w and s/w directly).
• I manage to get 100% of electric utilities in CA to put my product in 100% of customers' buildings [~12.9M customers]
• The utilities agree to pay me 50% of the saved costs of generation [~$17.82/customer*yr]
• A customer dashboard costs my business $35 installed.
• I take out 15% profit and have 10% overhead costs to run finance, HR, facilities, etc. 
• 35% of my workforce is engineering or other functions not directly customer facing / supporting.
• It costs $200k/yr to hire, compensate and retain each employee on average.

 Two key numbers come out of this:

• $453M - The cost to install the equipment at all the customers' locations. That's serious start up capital or a very slow ramp of the business. Starting isn't going to be easy.
• 23,000 - The number of customers per non-engineering employee that would have to be supported assuming I could start the company, pay off my debt and get to a steady state. If I'm paid actual savings, that means I need to get all the customers to actively use their dashboards and change behavior. The challenge of getting a diverse population (the state of CA) to sustainably change behavior over time with such a ratio is staggering.

As of that weren't enough, it would make sense for the power utility to shift their baseline over time rather than pay me for the same level of performance forever as it would be cheaper to address the problem themselves. This means that I'd not only have to get people to achieve good energy savings (target 10% on average - per the previous post), I'd have to increase this over time to avoid going out of business or avoid drastically shrinking the business.

I think I can throw this business plan out as a case where annuities are a bad business model.

However, that $453M number does suggest that selling h/w and analysis / customer feedback infrastructure to the utilities might be a better way to go. Maybe I could even write a game to make engagement fun.

Photo credit: Leften on Flickr ... not a picture of CA ...

How cigarette smoking could help save the planet... sort of...

Ok... not smoking per-se, but the 12V plug they built into every car to run the cigarette lighter.

Many of the electronic items in the home do not require 110V AC. If it has a big plug adapter or a power brick attached, the item is converting the 110V AC down to some smaller (something around 5 - 12V) DC current. Those conversions are not perfect and energy is lost.

What if you recovered those losses by having a single efficient conversion instead of many less efficient ones (or required that all converters be more efficient)?

Assuming that computer power supplies are representative of overall power supply conversion efficiencies, the average AC/DC converter is about 75% efficient. On the upper end, you can get ~90% efficient converters. So say a 15% difference in conversion efficiency between several average converters and one efficient one.

According to the DOE End Use Consumption of Electricity Survey (2001 - latest data), about 15% of a house hold's electricity usage goes to things that could, plausibly, run on 12V DC power. That was about 173.5 Million MWh of electricity. Improve that by 15% and you save 26 Million MWh of power.
The average output of a coal fired power plant is about 233 MW. So, for simplicity, if you assume 100% duty cycle, that 15% efficiency boost becomes the equivalent of 12.7 coal fired power plants.
While that is maybe not world saving (<1% of the 1445 coal fired plants in operation in 2008), that is ~5.5x the total Solar (thermal + PV) generating capacity in 2008... a bigger impact than solar has gotten us so far.

Where DC wiring, rather than just more efficient converters, might be more important is in Solar PV on homes. In that case, the DC output of the panel is converted to AC before being used in the home. That step has about a 90% efficiency.
However, many appliances then convert the AC right back to DC with all the losses noted above. Even with 90% efficient converters, that's a 19% efficiency loss over using the electricity directly from the panels.
Viewed another way, the AC wiring in your house is raising the price of Solar PV by almost 20%!

photo credit: David Baker (Flickr)

Mo' money, Mo' Money. Mo' Money.

A difficulty of the triple bottom line is the entrenched position that only profit matters. So justifying sustainability expenditures must occur in the context of return on investment (ROI). Redrawing the sustainability system diagram in terms of the profit aspect shows that not much actually changes:

Most of the considerations and feedback loops are still included because they all affect profitability in one way or another. However, since the focus is now on ROI, the message changes slightly to focus on comparing what each aspect costs vs what it brings. At a high level:

Contingency expenses vs Materials Cost

• Does it add more in materials or procurement costs than it saves in insurance, continuity plans, taxes / cap & trade costs, relocation costs and opportunity costs (business disruptions)? 
• Admittedly, the impact of one company on the overall environment is probably small which is why pricing the externalities helps (e.g. carbon pricing) as it focuses everyone on those externalized costs in a consistent, material way.

Utilities Costs vs Building Cost

• Does it cost more to add energy and water efficiency capabilities than it saves in operating costs? Studies say that the payoff is positive (3% - 7% increase in building costs for 10% - 50% decrease in energy usage)
• Not shown here but important for builders is the question of whether green buildings demand a premium in rental rates or have higher occupancy rates (they do by ~13% in $ and 3.5% in vacancy rate).

Productivity Gains & Decreased Training Costs vs Building Costs

• Does it cost more to add indoor environmental quality improvements (e.g. daylighting, thermal controls, exterior views, higher ventilation rates) than you gain through improved worker productivity and retention?
• It helps to consider that payroll costs are generally a much larger fraction of business costs than facilities + real estate costs. So if you can spend 7% in building cost to improve productivity of payroll by 2%, you will still come out very much ahead. Something like:
• For 1000 employees @ 250 sq. ft /ea in office space built in San Francisco is ~ $50M. Amortize over 30 years = $1.6M/yr. A 7% increase is ~$117k/yr.
• For the same 1000 employees @ $150k/yr in payroll costs = $150M/yr. If you can improve productivity by 2%, that is ~$3M/yr.
• ROI ~ 24.

So Mo'Money, Mo'Money, Mo'Money and sustainability really do get along.

Product positioning if you made a cleantech widget

In the last post, I used a system diagram to look at a picture of sustainability leverage points from the perspective of the owner. That can be turned around and used to look at the picture from the perspective of a cleantech vendor. Let's say someone like Redwood Systems who makes an LED lighting + sensor system that allows feedback to a building automation system.

Key messages can be tailored to the exact circumstances and interests of the building owner but two main themes seem to stand out around energy usage and environmental quality.

Reduced energy usage:

• drives down operating costs 
• Direct savings from the lower energy consumption of the lighting fixtures.
• Indirect savings from the improved efficiency with which the fixtures, HVAC and process equipment can be operated based on feedback that the fine grained sensor network provides.
• helps the planet and, thereby, your operating risks / costs
• Reduced energy usage lowers the company's carbon footprint, reducing its impact on the environment.
• A reduced carbon footprint, in addition to helping reduce the potential business continuity costs and impacts of climate change, also helps reduce potential liability for carbon tax or cap & trade costs.

Better control of environmental quality:

• improves productivity and profits
• Fine grained feedback control over the workspace allows for a more pleasant and, therefore, productive workplace. Even small increases in productivity provide large leverage when weighed against total payroll costs, especially for highly paid, specialized workers.
• improves worker retention
•  Deployed as part of a larger program for improved retention, having a comfortable workspace with a customizable, controllable environment decreases costs of turnover both in lost productivity and in direct training.

LEEDing to Better Building Control and Efficiency via Wireless Mesh Networks

LEED v3 has expanded the emphasis on measurement and verification (M&V) in order to offset concerns that green buildings don't maintain designed performance over time.

The rating system where this is most evident is in the LEED 2009 Existing Buildings: Operations & Maintenance (EB:O&M) If you dig through the credits with an eye towards the ones that:

• Require or could benefit from some sort of real time or on-going monitoring
• Could use a portable monitoring system comprised of sensors and small data network.
• Address the toxicity and recycle-ability of the sensor & networking systems

You find that something on the order of half of the credits (around 46 of 92 when I last checked) could be affected by having a good sensor system available.

Sensors, of course, need a communication network to feed their data back to a building automation system, (BAS) or building management system (BMS). If you are forward thinking and lucky enough to be engaged in new construction, then you can build many of these networks into the plan. Then when you meet the USGBC requirement for ongoing performance monitoring by following the EB:O&M certification route, you will be ready. For new construction, this is probably a good way to go.

However, if you're in the position of having an already complete building and you want to obtain EB:O&M, getting such a network in place could cost a considerable sum due to the wire routing involved. In such cases, using a low power wireless network would be preferable. Given the large area to be covered by a wireless sensor network and the large number of discrete sensors needed, this kind of application lends itself to a wireless mesh network (ala IEEE 802.15). Basically a network that uses the nodes to communicate with each other rather than requiring all units to communicate with a central access point. The more nodes (sensors) in place, the better the network becomes... and it's low power enough to run on batteries for months at a time... important if you need to pay someone to replace all those batteries.

UC Berkeley has pioneered work on this topic, coining the phrase "smart dust," and spun off at least one company (Archrock) that aims to address this kind of market space.