Thoughts on ENERGY 2013 conference


I just finished attending the ENERGY 2013 conference in Lisbon. The conference was a part of InfoSys 2013, which consists of several smaller conference all bundled together. Each day had one keynote and on panel discussion drawn from all the different conferences/tracks,  making for an interesting, and eclectic experience. There were perhaps 30 attendees for the ENERGY subconference, so I got to know several of the presenters.

I was presenting our paper on lessons learned from designing energy feedback visualizations for the Kukui Cup. Our three lessons about feedback visualizations is that they should be actionable, that domain knowledge must go hand in hand with energy feedback systems, and that this feedback must be “sticky” to lead to changes in behaviors and attitudes. While I was probably the only attendee focused on feedback visualizations and behavior, I got some interesting feedback from other energy attendees, such as finding additional ways to connect to undergraduates (e.g., beer :))

Below are my notes on some of the presentations I found noteworthy. So nice to be at a conference with open access to the proceedings so I can link to them directly!

Energy Aware Scheduling

Kanad Ghose presented on Dynamic Classification of Repetitive Jobs In Linux For Energy-Aware Scheduling: A Feasibility Study. 2.8% of electricity in the US is used by datacenters, and their research is on trying to find ways to reduce energy use in the datacenter environment. The basic idea is that some jobs are CPU-bound and others are I/O bound, so on a server with multiple CPUs, some CPUs can downshifted in voltage and frequency for I/O bound tasks (which spend most of their time waiting for I/O requests) with a consequent savings in energy. The other CPUs are kept at the highest performance level for the CPU-bound jobs. Each type of job (identified by the executable image) is classified, and jobs are scheduled by the kernel on the properly tuned CPU. Interesting work, and they are seeing about 5-10% reductions in energy use with small increases in latency. In the future they foresee servers in the data center communicating data about their loads (and predicted loads) to the HVAC system to further reduce energy use by preventing overcooling.

Voltage Sensors for Smart Grids

Chris Yakymyshyn from FieldMetrics presented on his work on Sensors for Smart Grids, which focused on the complexities of designing voltage and current sensors for the medium-voltage environment that are highly accurate. Utilities are typically required to provide electrical power within certain bounds of voltage and frequency. In the past, utilities had usually just targeted the center of the range for safety, but they have now realized that by reducing the provided voltage to the bottom of the regulated range they can save huge amounts of energy, avoiding the need to construct additional power plants! However, to skirt the edge of the regulated range, utilities need to actually measure the voltage they are providing so they can avoid fines for being outside the range.

One neat thing is that the sensors they have designed work optically,  taking advantage of the Pockels effect whereby an electric field changes the index of refraction of certain crystals. Their sensor produces polarized light, which is guided through multiple crystals, and a sensor at the other end measures the angle by which the polarization light has been rotated.

The results from their field trials with BC Hydro are equally interesting. One major application by BC Hydro is detecting energy theft. To detect theft, a power sensor is installed on the medium-voltage transmission line before a group of customers, and then after the group. Combined with smart meter data from the customers, the utility can determine how much power should have been drawn off the medium-voltage line compared to what the smart meters reported. In one neighborhood, approximately 27% of the delivered electricity was being stolen, and the majority of that was coming from (illegal) marijuana grow operations! This leads me to ponder how much energy we could save if growing marijuana was legal, which would allow for more outdoor growing, or at least energy audits of facilities. 🙂

Energy Storage & Vehicle-to-Grid (V2G)

Mark Apperley from the University of Waikato, New Zealand brought a wonderful discussion on energy storage and specifically vehicle-to-grid (V2G) storage. One of the conference panel discussions focused on energy storage. The discussion was quite wide-ranging, and I found the following points interesting

  • Mark pointed out that we all have a storage system in our homes for a different resource: toilets. Toilets store water, dispensing it at 140 l/m, but refill at 30 l/m. The water storage provides two benefits to water-providing utility: it smooths out the load generated when people flush, and it also provides an “infrastructure improvement” since the water pipe coming to homes is not sized to provide water at the rate needed to flush. Electricity storage would also provide these same two qualities. For example, as electric vehicles become more widely used, the distribution lines to neighborhoods may become overburdened as adding an electric vehicle roughly doubles the electricity use of a home. In a neighborhood with many EVs, some vehicles may discharge to provide their neighbors with power which the utility is not able to provide with the existing distribution lines.
  • In talking about the growth of renewable energy, Chris Yakymyshyn pointed out that fossil fuel power plants need to run a certain percentage of the time in order to make a profit. If they are only being used a small percentage of the time to support intermittent renewable energy sources, they will shut down and go bankrupt.
  • I shared point made by Mark Duda, a founder of residential-solar installing company RevoluSun in Hawaii. He pointed out that since electricity prices are very high in Hawaii, PV is quite cost-effective for many homeowners, some of whom also install a battery storage system so they can go completely off the grid. Hawaiian Electric (like all utilities) has large fixed costs (power plants are expensive!) that it has to pay regardless of how much electricity they actually generate. Thus as more people are able to switch to solar, Hawaiian Electric will have to spread the fixed costs over fewer customers, leading to higher rates. This makes solar cost effective for even more homeowners, who then disconnect from the grid, which could lead to a spiral when the utility can no longer afford to pay its fixed costs.

Mark also gave a keynote talk on his research into V2G in New Zealand. The concept of using electric vehicles as a storage system for the grid is not new, as it was first suggested by Kempton and Letendre in 1997. Two important issues for V2G are that the electric vehicles need to be plugged in to be a resource for the grid, and that the decision on whether to charge from the grid or discharge to the grid requires knowledge of the planned usage of the vehicle (e.g., when will the owner be driving home?).

The promise of V2G is that vehicles are only used a small portion of the time. In NZ, vehicles are estimated to be used only 4% of the time, providing a lot of potential time for grid backup. Mark has created a fine-grained simulation of electric vehicle use for grid storage in NZ, with a 1 minute time scale, individual vehicle simulation, and real utility load data (we can only dream of this level of data in Hawaii!). The simulation also takes into account the gradual adoption of electric vehicles.

Based on the simulation results, with 400,000 EVs, V2G reduced peak energy generation requirements, and flattens out the demand curve. Unfortunately, it did not actually reduce the height of the peak load: while EVs can be helpful for storage, they also increase demand for electricity for their use as transportation. As an amusing aside, Mark said that one of his student’s had computed that if all the laptops in NZ could be linked to the grid, they would be able to handle the national load for a few minutes 🙂

It would be great to see a simulation of how V2G would work (or not) for Hawaii, but it would require a lot of data that is not available outside of Hawaiian Electric.

Mahalo to all the participants and organizers of ENERGY 2013!

Meaningful Play 2012

For the past 4 days I have been attending the Meaningful Play 2012 conference. MP is an interesting mix of game design and game analysis, with a heavy focus on serious games, games for learning, games for impact, or whatever you want to call them. The 2012 proceedings are available online, but surprisingly not linked off the main page. I was there presenting our paper Beyond kWh: Myths and fixes for energy competition game design, which explains the counter-intuitive energy use from the 2011 UH Kukui Cup, and our investigation into the methodology of energy competitions in general. I also demoed the Kukui Cup at the MP game demo session, and there were a lot of good games there.

The following are some quick thoughts on the conference from my perspective, with special emphasis on things relevant to our work on the Kukui Cup and serious games for sustainability.

Donald Brinkman from from Microsoft Research gave the opening keynote. He’s one of the leaders of the Just Press Play project, which is a game experience for game design students at RIT intended to reduce student attrition and increase interaction between students. There are many parallels between Just Press Play and the Kukui Cup: players can earn achievements for certain actions, there are real world events that players can get credit for attending. They originally handed out 25 digit attendance codes on cards, but players were (understandably) not pleased about typing in long codes to get their achievements. Their latest iteration of the system gives a QR code to each player, and admins scan the codes using a smartphone app in order to award achievements. This is a nice solution to the problem, though I wonder how many students will forget or lose their QR code. I have a feeling that would be a problem at UHM, where many students seem to wander the area around the residence halls with just their ID card and keycard. I’m also curious to see how the heavy emphasis on badges, with no points or leaderboard will play out. Once you have many badges, I worry it will make badges somewhat meaningless (see Achievement Unlocked 2).

One aspect of the Kukui Cup that we have sometimes bemoaned is the fact that it is optional, and so only a portion of the 1000+ residents in Hale Aloha participate. However, something that came up many times during the conference is the idea that being optional is good. In fact, some presenters believe that mandatory play is not really play at all.

There was a presentation by Steven Dodds, Carrie Heeter, and Andy Simon about civic gaming in San Jose that really piqued my interest. The team presenting have run “budget games” where small groups sit at a table and have to make decisions about what city projects to fund, which to cut, and how to raise revenue. The results of the games have then been largely incorporated into the mayor’s budget request! The most fun workshop I attended was titled “Pervasive and Environmental Game Design” by Jeff Watson from USC. The topic was really about games for action: instead of simulating the world or telling players how to change it, make the game actually be about taking action. The audience was broken up into small teams, and given the objective of creating a working game prototype that addressed some issue regarding the MP conference itself. Our team designed a game intended to increase the networking at the conference, which we called Network Bingo, where each player has to collect business cards from other attendees, and try to fill up a bingo card with organizational roles across the top (student, professor, designer, etc) and application area going down (health, sustainability, etc). We didn’t quite get to the point where we had a playable prototype (only one team did), but the experience was awesome and opened me up to new possibilities in this space. I’d really like to create a analog game that lets the players explore Hawaii’s energy and sustainability issues using these techniques.

One thing that struck me after seeing all the awesome games and research going on at the conference is how much we could improve the learning potential of the Kukui Cup by making it more “procedural rhetoric” (Ian Bogost’s term). While we do have some activities like the Energy Scavenger Hunt where we teach players things implicitly as part of the game play, still too much content relies on watching a video and answering a question, which is only a game by from a very charitable viewpoint. This orientation was necessary to meet our requirements, since sustainability is a enormous topic and given our available resources making a game for each subtopic would have been completely infeasible. But as the Kukui Cup matures, we need to start making more and more of the experience gamelike and less like traditional teaching.

Meaningful Play was a blast (even if it rained a lot!) and I look forward to the next one in 2014!

Malasada Bread Pudding

We’ve all been there (if you live in Hawaii): you go to a party, multiple people bring boxes of malasadas, and at the end of the party there are way too many left over. Throwing them out would be criminal, but they never taste as good as they did when they were fresh and hot.

If you have room temperature malasadas, you can microwave them for ~15 seconds and get something pretty decent. You can also put them in a toaster oven for a while, which turns the sugar into something crisp and creme-brulée-like. But if you have a whole bunch, you may get tired of that too.

I present to you an innovation in malasada-reuse: the malasada bread pudding. It makes sense, since malasadas are eggy, and bread pudding can be made with brioche or other egg-based breads. I had the idea for this, but the recipe is all Yuka. We made some this weekend, and it came out great. With Mardi Gras (aka Malasada Day) coming up, give this recipe a try:

Yuka and Robert’s Malasada Bread Pudding


  • 6 leftover malasadas
  • 1/2 cup raisins, dried cranberries, or chocolate chips (optional)
  • 4 eggs, beaten
  • 2 cups whole milk
  • 1/2 cup white sugar plus more to sprinkle
  • 1 teaspoon ground cinnamon
  • 1 teaspoon vanilla extract
  • a pinch of nutmeg


  1. Preheat oven to 350 degrees F (175 degrees C).
  2. Break malasadas into small pieces into an 8 inch square baking pan or individual ramekins. Sprinkle with raisins, dried cranberries, or chocolate chips (optional).
  3. In a medium mixing bowl, beat eggs, add cinnamon and a pinch of nutmeg. Then add milk, sugar, and vanilla. Beat until well mixed. Pour over bread, and lightly push down with a fork until malasadas are covered and soaking up the egg mixture.
  4. Bake in the preheated oven for 45 minutes, or until the top springs back when lightly tapped.

Enjoy! Wasted food is an abomination, and making use of food that would otherwise be wasted reduces your carbon footprint. 🙂

Zuma Blitz and the Kukui Cup

I’ve been playing a fair amount of Zuma Blitz on Facebook. Zuma Blitz is a Flash game from Popcap, makers of many popular Flash games, including the original Zuma. While playing, I have been thinking (occasionally) about what we can learn from “normal” games like Zuma Blitz.

Zuma Blitz mechanics

Zuma Blitz involves a frog that you control in the center of a game board. You can rotate the frog in any direction, and clicking the left mouse button causes it to fire a ball of a particular color (chosen randomly). The game board has tracks on it, and balls of 4 colors are released onto the board at varying rates. The balls follow the tracks, and if the balls reach the end of each track, then the game is over. When the frog fires a ball at the balls on the tracks, if a match of 3 balls in a row of the same color is made, those balls are removed from the board. In addition to the normal balls, there are special balls such as multiplier balls, time balls, etc. Matching these balls affects game play in some positive way. This might sound very complicated, but after about 20 seconds of game play you will see how it works.

Each game lasts for 1 minute, so game play is highly frenetic. There is no time for strategy, balls must be fired very quickly for good scores. The game records 3 different values for each player: score, mojo, and experience points. Score is recorded for each game played, and the highest score for each player for each weekly tournament is displayed in-between games. A histogram of scores (in 50K increments) is recorded, with each bin associated with a different “spirit animal”, and as additional scores are accumulated in each bin, the player achieves different “levels” of spirit animal. This provides a little additional interest for the player, and also shows a historical record of the player’s scores.

Mojo and experience points (abbreviated XP) are accumulated at the end of each level, based on how many balls were matched (which is different but correlated with the score achieved on a game). Mojo can be used by the player to buy powers that can be used to make game play easier, but the cost is recurring for each game they are used in. Powers generally cost more mojo than the player can earn each game, so powers must be used sparingly.

As XP is earned the player reaches different levels. Upon reaching a level, something new is awarded to the player (a new power, a new spirit animal, etc. See this list of levels for more details). Since XP is awarded after each game, no matter how low the score, less skilled but persistent players can improve their scores by achieving higher levels. Zuma Blitz also has idols that are awarded for reaching an XP level, and the idols can be used to buy things in the store (extra lives, mojo, etc). For impatient players, idols can be purchased using Facebook credits (bought using real currency), this is presumably one revenue stream for Zuma Blitz.

When starting Zuma Blitz, the player is given 5 lives, and each 1 minute game takes one life. These lives regenerate based on real world time (starting at 8 minutes). This prevents the user from playing more than a certain number of games in a row, as the lives have to regenerate. Higher levels award the player more lives and reduce the length of the regeneration timer.


Zuma Blitz parallels and lessons

Surprisingly, Zuma Blitz (ZB from here on) has several parallels with the Kukui Cup (KC from here on). Among the ones I have noticed:

  • Players cannot play ZB continuously due to the lives and regen timer. This requires them to come back later to play. Many KC activities require a human administrator to verify that the activity was completed properly, requiring players to return later to see if they got their points. We have worried that this delayed gratification might be off-putting to KC participants, but ZB has deliberately picked this approach (though this is for continuation of the game, rather than the awarding of points).
  • ZB has 3 different metrics being collected (score, mojo, XP) that are interrelated but different. KC has both points and lounge energy usage, which are different and we hope are interrelated. We have been concerned about the complexity of having 2 metrics, but clearly popular games can be similarly complicated.
  • ZB is also based on weekly tournaments, the way KC has weekly rounds. The layout of the ZB game screen (where the tracks are, background image) changes each week.
  • ZB has a store and idols, which is similar in some ways to our raffle and raffle tickets that are earned through points.

Some potential lessons from ZB:

  • The special balls that appear on the board disappear after a certain period of time. If you manage to match them a couple seconds after they have disappeared, you still receive the special value for the ball. In essence, there is a grace period. As a player, this kind of generosity is greatly appreciated, something frustrating (missing a special ball by 1 second) becomes enjoyable. KC already has this generosity in some ways, for example all lounge residents receive points when the lounge makes their energy goal, even if they did not participate in any way. We should continue to look for ways to make KC “generous”.
  • When you first play ZB, it shows all your Facebook friends that have also played the game, their highest score this round, and their stats. It would be good if KC could scan participants’ Facebook friends to see if there are any matches among the residents of the participating dorms. If there are matches, the participant could be given the chance to message them on Facebook to encourage them to participate. You could even get points for doing this, perhaps (or will that just encourage spamming?)
  • Unlike the plan in KC, ZB does not post things automatically to the player’s Facebook wall. Instead, for every interesting event (new high score, winning weekly tournament, new spirit animal), there is a button that says “Share” (or “Gloat” if you win the tournament), and that prompts for text to go along with a post to your wall. We had briefly considered and rejected this technique in KC (I believe I rejected it out of hand by saying something like “are we going to have a Share button in every dialog box??”), but if ZB is doing it then perhaps they know what they are doing. One difference is that ZB is runs in perpetuity, while KC is focused on a 3 week period. A compromise might be a single daily automatic post from KC, and then share buttons provided for noteworthy events.
  • ZB’s changing weekly game layout is another way that ZB encourages players to return frequently. Perhaps we could have a different color scheme or background image for each round. Perhaps the rounds could have names/themes?

That’s all I can think of so far. It might be interesting to look at other Facebook games to see how they make use of the functionality of Facebook, as well as their own game design.

Thoughts on HICSS 44 (2011)

I just got back from the Hawaii International Conference on System Sciences, aka HICSS. This conference has been running for 44 years. General information about this year’s HICSS can be found here, and the proceedings will eventually be here.

This was my first HICSS, which is kinda strange seeing how long I have been in Hawai`i. It was held this year at the Grand Hyatt Kauai, which is pretty luxurious. I guess the idea is to hold it at resort that will be a draw for participants, and provide enough amenities that attendees don’t feel the need to wander off.

The first thing that struck me about HICSS is the incredible diversity of sessions going on. The conference is organized in as a bunch of tracks (high-level topics), which are then broken into about 60 minitracks. The minitracks can last a whole day (4 sessions) or be as short as a single session.

The result is a huge smorgasbord of papers. Each day, there are 15 parallel tracks, ranging all over the place: education, social networks, cyber security, location-based marketing, power systems, and many more. This can be good if you want to check out a diverse set of presentations, but to me it makes HICSS feel more like a conference of mini-conferences than a unified whole. This is quite different from a conference like Ubicomp, which is vociferously single-track so that every attendee can attend every session if they want to. Naturally, Ubicomp accepts far fewer papers than HICSS.

The minitrack I was attending (Information Systems and Decision Technologies for Sustainable Development) didn’t start until the second day, so on the first day I just went to sessions that looked interesting. Just deciding which sessions to attend is quite a task: 15 rooms * 4 sessions a day = 60 paper titles to look at!

I started with the Future Electric Power Systems (smart grid, more or less) minitrack. This minitrack was located in a standalone building at the Hyatt that is used as a nightclub. So the attendee chairs were set up in a sunken dance floor, and the presentation slides were shown on one large TV embedded in the wall, as well as 16 smaller TVs distributed around the ceiling (like one might find in a sports bar). This was kinda bizarre, but amusing.

The power systems minitrack has been running for 15 years, so the attendees seemed quite familiar with each other, and had their conference process down pat. The papers I saw were interesting, though more traditionally smart-grid-oriented compared to our Kukui Cup work. Unfortunately, the proceedings (which will be freely available) are not yet online, so I cannot link directly to papers.

  • A case study on the expected impact of PHEV vehicles on electricity consumption, using a new community in South Korea (A Case Study on the Grid Impact of PHEVs to Sample Distribution Power System by Dong Joo Kang and Sunju Park)
  • An algorithm for detecting “load pockets”, which are areas on the grid that are constrained by transmission such that generation facilities could raise their prices and electricity users would have no option but to pay the higher prices (Clustering of Power System Data and its use in Load Pocket Identification by Katherine Rogers and Thomas Overbye).
  • An analysis of locational marginal carbon intensity of generation (how much additional carbon will be emitted by increasing demand by 1 kWh in a particular location at a particular time) on the eastern part of the US. The results are somewhat surprising, in that areas that are heavy coal users might actually have lower marginal carbon intensity because if they had additional demand they would import power from generation facilities with lower carbon intensity. The presenter related the marginal intensity to Renewable Portfolio Standards, which provide subsidies for production of renewable energy. Currently subsidies are independent of carbon intensity, but the authors argue that they should be higher (pay more for renewable energy) in places where the marginal carbon intensity is high, and lower where marginal intensity is low. This would encourage the buildout of renewable generation in places where it would reduce carbon emissions the most (Locational Carbon Footprint and Renewable Portfolio Policies: A Theory and its Implications for the Eastern Interconnection of the US by Aleksandr Rudkevich, Pablo A. Ruiz and Rebecca C. Carroll).
  • An investigation into what is really happening in loads, starting with hot water heaters. The presenter argued that there has been a lot of research into the dynamics of generation, but very little in the dynamics of loads, which will be critical for any type of demand response program. In the ensuing discussion, I learned a new term: demand subscription. This is the idea that rather than being metered for use, customers subscribe to a certain amount of electricity (not sure if it is measured as power, energy, or both) and then it is up to the customer to figure out how to live within that subscription. So the utility would only communicate with a smart meter, not reaching beyond the meter to smart appliances.

I also had time to attend some talks in the social networking track by members of LILT (my former research group): Dan Suthers, Kar-Hai Chu, and Devan Rosen. I was familiar with some of the outlines of the Traces work, but it was good to see it discussed in a public forum.

The minitrack I presented in was called Information Systems for Sustainable Development. I presented our paper describing the design of the Kukui Cup. It seemed well received, with most of the questions revolving around how to get students involved and how to keep them aware after the competition in order to sustain behavior changes. Eric Paulos suggested we should provide Kill-A-Watt meters to some residents in May 2012 before they move out of the first-year dorms, and then follow up with them on whether and how they used them in their next living situation.

Two other presentations in our track that I found interesting:

  • Hendrik Hilpert, a PhD student from Göttingen University presented work on computing products’ carbon footprints automatically using vehicle mass airflow data (obtained via OBD2) fused with GPS data. This combination allows one to compute how much carbon is being emitted, while the GPS data allows the carbon to be allocated to different products that might be on the same delivery vehicle as it makes a series of stops. They even cited my older literature review in their paper, würd! (Real-Time Data Collection for Product Carbon Footprints in Transportation Processes Based on OBD2 and Smartphones, by Hendrik Hilpert, Lars Thoroe and Matthias Schumann).
  • Eric Paulos, assistant professor at CMU presented work on Citizen Energy. Citizen Energy is the idea of changing people from just being energy consumers into more active participants in the generation and use of energy. They have made a bunch of cool devices, like a Seasonal Energy Lamp. The lamp is connected both to grid power and to solar and wind turbines, and it changes the color of the emitted light depending on the source (orange for solar, blue for wind, etc), making people more aware of where their energy is coming from. These design experiments seem really complementary to the Kukui Cup, possibly providing additional ways for participants to become more energy literate. (Citizen Energy: Towards Populist Interactive Micro-Energy Production by Eric Paulos and James Pierce).

Unfortunately, our minitrack had fairly low attendance (perhaps 8 attendees at peak, of whom half were presenting in the minitrack), so I don’t know how it will fare next year. All in all, it was a worthwhile experience, but was a bit of a comedown after BECC 2010.

Hawaii election resources

I’m filling out my absentee ballot for the general election, and while I knew how I was going to vote on the federal and state legislative candidates, that’s only about 1/6th of the ballot. So I was tracking down some resources for finding information about candidates and issues and thought others might also benefit. Note that the official Office of Elections website is pretty useless for this type of info.

For those looking for information on federal races, Project Vote Smart is pretty cool: you answer questions about issues, and it tells you how similar the candidates running in your area are to your views.

Board of Education

The League of Women Voters has a rather comprehensive list of candidates running in the general election, including the Board of Education. Some candidates have provided statements and campaign websites, some have not.

Olelo (excuse my lack of diacriticals) has a nifty Candidates in Focus site where you can watch a video statement from many of the candidates.

The Star-Advertiser has made BoE endorsements, though read the comment from one candidate that says he was never even contacted by the paper.

Constitutional Ammendments

On the amendment to switch the BoE from elected to appointed, the League of Women Voters has a decent Pro-Con PDF that lays out the issue. I found the historical documents from 1970 (last time such an amendment was proposed) that oppose appointment not very helpful, since they didn’t clearly articulate the reasoning behind the position.

The LWV has another pro-con PDF on the tax rebate requirement amendment.

C&C Charter Amendments

Again, the LWV comes through. Council member Dela Cruz has a presentation [PDF] that explains in more detail what the charter changes mean (without any pros or cons). The LWV has a pro-con PDF that covers all 6 amendments.

I hope others find this information useful.

Notes from SmartGridComm 2010

Last week I attended the first Smart Grid Communications conference. I was presenting our paper on WattDepot. The presentation went well and there were several questions afterward. One point that I got several questions about was our requirement to support rapid data collection (sub-minute), since that is much faster than most commercial meters support. In retrospect, I should have emphasized our application domain (the Kukui Cup) more in the presentation, which might have helped to explain that requirement.

The following are some of my notes from the conference:

  • There were 102 papers accepted at the conference (40% acceptance rate), and 441 registrations. The mix was roughly 44% academic, 31% industry, 20% R&D, and 5% government.
  • The conference was held at NIST, and throughout the building were NIST clocks that presumably were very accurate. 🙂
  • There is a Smart Grid Consumer Collective, which sounds like an organization we should keep an eye on.
  • There are apparently standard power network topologies that can be used for analysis and research, such as the IEEE 300 bus power flow test case.
  • Some power industry slang I was not aware of: “big wire” relating to electricity distribution, “little wire” relating to communication networks. As in “the Smart Grid is all about the little wire people working with the big wire people.”
  • Georgios Kalogridis presented work on “Privacy for Smart Meters: Towards Undetectable Appliance Load Signatures”. The basic idea being that if the utility has fine-grained data about energy usage, they can determine a lot about what the consumers are doing. Kalogridis et. al. propose a system where a rechargeable battery is located in the home, and can be used to mask the signatures of energy use by charging and discharging at appropriate times. They cite this interesting paper by Elias Quinn that lays out all the potential privacy issues related to fine-grained energy usage data.
  • Came across a reference to Stanford’s PowerNet project, which aims to measure the “energy consumption of enterprise-style computing infrastructures”. Looks cool, paper here.
  • Hironori Nakanishi from the Japanese government reported on the Japanese perspective on the smart grid. Apparently Japanese utilities were not that eager to pursue smart grid upgrades because on average a Japanese consumer has 16 min/year of power outage, compared to the US average of 162 min/year. However, the Japanese government set the target of 25% CO2 reduction by 2020, which will require 28 GW of new solar power.
  • I also had not heard about the Hawaii-Okinawa partnership on clean energy.
  • One of the reasons that demand-side management is being pursued is for “peak shaving” by shifting some appliance loads to off-peak periods. Unfortunately, if all the smart appliances decide to shift their loads to the start of the off-peak pricing period, then you get a rebound peak. This seems like a challenging problem, barring real-time pricing that takes the rebound peak into account.
  • Jay Taneja presented work from UCB on shifting appliance loads to make maximal use of fluctuating renewable energy.The idea is that certain thermostatically-controlled loads like a refrigerator store electrical energy as thermal energy, so they can be scheduled based on the availability of renewable energy (in their study, wind energy). So if there is excess wind energy available, the fridge compressor could run more frequently, and vice versa. Bringing data about grid renewable energy production is something we have been thinking about from the consumer human interface perspective (the carbon “traffic light” concept), but they are working on making actual appliances sensitive to renewable production. Very cool.
  • In total, I gave out 11 business cards, and 2 REIS brochures.

Next year the conference is in Brussels. Paper deadline is April 4, 2011.

Oreo Cheesecake Pudding Cup Recipe

I got this recipe from a co-worker at LavaNet a few years ago (Hi Tim!). It makes a lot of  cups, and has proven to be a crowd-pleaser. Mahalo to Yuka for transcribing the original version from a printed fax to electrons. Enjoy.

Makes 36 cups


  • 1  box of cook and serve chocolate pudding (5.9 oz box)
  • milk for pudding
  • 1 package of Oreo cookies
  • 2 packages of cream cheese at room temperature (8 oz each)
  • 3/4 cup sugar
  • 2 eggs
  • 1 tsp vanilla extract
  • chocolate chips (optional)
  • Cool Whip/whipped cream (optional)


  • 3 muffin tins (if you have less than 3, then you will have to bake in batches)
  • 36 paper muffin cups
  • Mixer (hand or stand)
  • Mixing bowl
  • Saucepan


  1. Cream together sugar and cream cheese in bowl with mixer.
  2. Add eggs and vanilla extract.
  3. Line muffin tins with muffin cups.
  4. Place 1 Oreo cookie at the bottom of each cup. You can put a whole cookie in each cup, or twist them apart and put half a cookie in each. If you have less than 36 Oreos (but more than 18), splitting the Oreos is a good way avoid buying another package.
  5. Spoon one heaping tablespoon of the cream cheese mixture into each cup on top of the cookie.
  6. Bake at 350° F for about 10-12 minutes, or slightly golden brown.
  7. In the meantime, make the chocolate pudding as directed on package.
  8. Take the muffin tins out of the oven, and let them cool at room temperature.
  9. Also allow the chocolate pudding to cool slightly.
  10. Spoon the chocolate pudding onto each cup.
  11. If using chocolate chips or Cool Whip, add them now. If using whipped cream, add just before serving.
  12. Refrigerate until set.

DVIator + DVI Mini DisplayPort adapter = No Go

I have one of the original Apple 22″ Cinema Displays. These monitors use the Apple Display Connector (ADC), which bundles together DVI video, USB, and monitor power into a single cable. It was an interesting idea (presumably derived from/inspired by  the way NeXT cube displays worked), but since it wasn’t an industry standard, only Mac video cards had the connector, and only on desktop systems like the PowerMac G4.

If you wanted to connect an ADC monitor to systems that had DVI video output (like the PowerBook G4, and later MacBook Pro), you needed a special adapter that split the ADC into DVI, USB, and provided power. Initially, the DVIator from Dr. Bott was the only affordable solution, so I bought one. It’s served me very well over the last 7 years, and Dr. Bott even replaced mine once when it didn’t work with my aluminum PowerBook G4.

Apple has once again changed their preferred laptop display connector, and now uses the Mini DisplayPort format. MDP provides a teeny connector that can still drive 30″ monitors and the latest versions can also output audio (like HDMI).

Unfortunately, this means that unless you have a Mini DisplayPort monitor (Apple sells one), you need an adapter to connect your monitor to a MDP laptop. For those with DVI monitors, Apple sells a Mini DisplayPort to DVI adapter, which solves the problem. However, I found that adapter does not work with the DVIator, confirmed by this Apple Support forum post, another at MacRumors, and an email from Dr. Bott support. Based on the forum posts, apparently the Apple ADC to DVI adapter ($99!) does work with the MDP to DVI adapter, but I haven’t tested that myself yet.

So, bottom line: if you have a DVIator, an ADC display, and a computer with MDP output, you’ll need to either buy the Apple ADC to DVI adapter (in addition to the MDP to DVI adapter) or buy a new monitor. Bummer.

Cross-origin data access from JavaScript

WattDepot features a RESTful API that emits XML, and supports the Google Visualization API using the Google-provided Java library. There is a Java client library that makes it easy to write WattDepot clients in Java, and Google provides a library for JavaScript clients using the Google Visualization API. A several Java clients have been written and several JavaScript clients have been written.

Yichi Xu is working on a GeoMap visualization for WattDepot, and it needs to use the REST API rather than the Visualization API. This means he had to query the REST API directly, and parse the resulting XML. He quickly ran into the same-origin policy in JavaScript. In short, scripts running from a particular domain can generally only access resources from that same domain. This makes sense, because you don’t want any random web page you browse to have access to all your email just because you have a Gmail window up. However, from a developer’s perspective, this is a big when you want to use an HTTP API. Yichi’s gadget is loaded either locally or from Google’s servers, so when it tries to perform an HTTP GET to the WattDepot servers, it fails due to the same-origin policy.

There are a few workarounds for this problem, and Nelson Minar provides a good introduction. You can use proxies, but that’s gross. The most common solution makes use of a loophole in the same-origin policy: you can load JavaScript code from anywhere (just not data). So if you wrap your data so that it looks like code, then you can violate the same-origin policy. If you are providing the data in the JSON format, once wrapped it becomes JSONP.

Right now, WattDepot doesn’t support JSON representations (though it may in the future), so the JSONP trick is not available to us. Luckily, Yichi came across this draft from W3C on Cross-Origin Resource Sharing. CORS allows servers to emit HTTP headers that indicate how browsers should restrict access to the resource. The header can open things up so anyone can use the resource, or only certain other domains. However, this requires browsers to act on the header, luckily Firefox 3.5 and the latest Safari both implement this (the Firefox page has an excellent discussion of CORS). For now, supporting Firefox 3.5 and Safari is acceptable, so WattDepot just emits “Access-Control-Allow-Origin: *” for all requests. In the future this will be cleaned up to only emit this for public sources, and also provide JSON and JSONP representations for easier use in JavaScript.