New Daedalus

One of the edgier concepts in computing has been the Personal Area Network, the network that surrounds a person. Seemingly way out there, the PAN is already surprisingly pervasive. What we need is the Personal Area micro Grid to go with it.

I first saw a PAN in an IBM proof of concept in the mid 1980’s, in which a small computer hidden in the heel of a shoe used body conductivity and perhaps sweat, for all I remember, to transmit information, Wearers of the shoe were able to exchange contact information by means of a simple hand-shake. This demonstration was half creepy, and have Maxwell Smart.

Today’s PANs are less exotic. Point to point networking between Bluetooth headsets and personal devices, whether they be phones, PDAs, or music players, make up the bulk of systems. The occasional user has even figured out how to share contacts phone-to-phone, or PDA to PDA.

Niche applications are creeping in to expand the PAN. When my son Josh worked in the Cleveland Clinics spine center, he described wired interfaces enabling people limited remote control of their own paralyzed bodies. With paternal sensibilities raised, I noticed engineering grads building open source responsive homes for the handicapped, using Bluetooth receivers cannibalized from old headsets.

Many people carry a surprising number of electronic devices with them every day. Charging them up requires a rats nest of different chargers. These chargers are as cheap as they can be made, and often draw nearly as much whether the device is plugged in or not. Keeping these devices charged throughout the day would keep them unplugged at night, as well as keeping them ready to use.

Meanwhile, personal power generations has slowly been creeping into society. My daughter spent the money from one of her summer jobs for a solar backpack when she was in high school, demonstrating her cred as a math and computer aficionado. Scott eVest markets a solar jacket to go along with the wiring harnesses in their TEC PAN.

But solar is not enough.

Recent reports talk of systems to generate power from kinetic energy. Science reports normal body movement. One system is reported to generate 13 Watts while reducing the effort of walking. Looking like a garden variety knew brace, the system harvests energy while reducing effort. At the end of a stride, a person must exert energy to slow his moving leg. The brace's generator helps slow the leg for the wearer, capturing energy in much the same way that a hybrid car harvests power from braking.

Others are working on bra-based generators. One lab is capturing swing and oscillation in a complex fabric-based generator. Another effort is focusing on piston-like energy capture from the brassiere straps. The [female] engineer note that different women have different power generation potential; I observe that there may be advantages to keeping that iPod set for dance tunes….

Microgrids use local energy production and storage to be self sufficient. The best reliability comes from a mix of technologies, with different performance characteristics. We have just begun to explore that the Personal Area Micro-grid might look like.

If a performing electric car were to arrive today, with adequate batteries at reasonable cost, it could well push today’s non-transactive energy infrastructure over the edge. Usually I write about intelligent building agents; when I write about the power grid, it is to discuss transacted energy purchases between those agents and an intelligent transaction grid. Today, I am going for those transactions on that grid, but leaving out the building. But first, a little on the building with cars.

There a lot of hopeful scenarios in which peak shaving is enabled by commuter cars plugged into office buildings. Peak shaving, initiated by what are called Demand-Response (DR) signals from the grid, is when buildings lessen their electrical demands to avoid peak periods of energy use. The story goes that we will go to work, and plug in our cars. When the DR event arrives, the building will run off the combined car batteries, reducing demand on the grid.

DR is very important for today’s grid, because the power supplied at the peak is the most expensive and usually the dirtiest to generate. I have seen numbers suggesting that as much as 17% of the grid’s capacity is used for less than 120 hours per year. If we manage peak electrical use, we have effectively grown the power grid for free.

Cars and their batteries, however, will never be an effective peak shaving tool for office buildings. Leave aside for the moment all HR-related issues associated with employers paying for commuting costs, and look at the people. Peak load occurs in the afternoon, and extends into the early dinner hour.

If I live some distance from my employer, will I be willing to end each day with a low charge on my car? Only until the first day I run out on the way home, perhaps because of an unanticipated need to attend a school event for my children, or to attend to a medical issue for my parents, or even to pick up some supplies for a social event. In any case, the first time it happens, I will resolve to park away from the building thereafter.

If I live close to work, I will arrive with my car already charged up. DR participation, always in the afternoon, will leave me always wondering whether I am subsidizing the company. The first time I am turned down for a raise, this thought will begin festering into a general resentment of my employer. Sub-vocal mutterings with phrases such as “blood-sucking leeches” come to mind.

Whether I live far away or whether I live close in, sooner or later I will leave early to head off for a summer (most DR events are during warm weather) weekend at the beach and find that despite my plans, my employer and its building have drained my car.

No, we cannot turn to electric cars to solve the DR needs of our office buildings. Not if actual people are involved. Perhaps if we make sure that our grid is intelligent and two-way transactional we can see a way past this.

I will try to write soon on what intelligence is needed, in grid and car, for more realistic use of more than a few electric cars.

I was corresponding with someone from the algal biodiesel group the other day. Genetically modified algae is one of the more intriguing fuel strategies in the mid-term. The short version is to add some oil-production genes from some other plant to fast-growing algae, scoop out algal mats and process into fuel.

Traditionally, algae has been seen as something to grow in plants about the size and distribution of this year’s boondoggle, the corn ethanol plant. Instead of large parking areas for constant transportation of corn, large shallow vats of algae would soak up the sun. Eliminating the need to transport the raw material to the processing plant would be yet another advantage to this process.

Some have suggested that the proper place to build the facility is by a coal plant. Algae grows faster in a high CO2 environment. The CO2 would get sequestered into new biomass, and then converted to biodiesel. The CO2 would make it into the atmosphere eventually, but not until it had done double duty for electricity and transportation.

But I thought, why stop there?

All kinds of moderately complex processes are now being built into small microprocessor controlled autonomous systems. If one could automate the production of Biodiesel on the rooftop, then local diesel generators could run on site generated fuel.

I do not imagine that this process would ever provide all power for, say, a commercial office building. It could, however have a place in zero net energy buildings and in local self-reliant microgrids.

Many organizations, from the AIA to ASHRAE, from the US department of Energy to the UN Environmental program, are chasing after the Zero Net Energy Building (ZEB). The ZEB uses a variety of strategies centering around local generation, storage, and conversion of energy to limit its purchases from the power grid to when the prices are right. The ZEB will likely make use of internal DC to eliminate DA/AC/DC conversion penalties on each source of energy. The ZEB building may well have PV, ST, Wind, and generators, mixing and matching as needed.

The problem with most of these local renewable energy sources is that they are unpredictable. As has been well demonstrated by the German Kombikraftwerk effort (search the archives), you can build a reliable grid almost entirely of unreliable sources as long as they are unreliable in different ways at different times.

Why not BioDiesel generators in the building? Why not algae vats and automated fuel production in the building? I do not see such a system being able to carry the building on its own, but if called on occasionally, as diesel generators are now, perhaps the tank could be filled in the interval.

So, why not Algal Biodiesel in the Building?

Sustainability initiatives come in four kinds. No harm initiatives accomplish something, but perhaps not as much as their proponents think. Let’s pretend initiatives make people feel good, but with reckless disregard for the actual results. Let’s pretend initiatives, like corn ethanol, may well do more harm than good. Yeah but initiatives would work well, maybe very well, but for some reason, you can’t get there from here. Usable initiatives are the few remaining that are simple, cost effective, and uncontroversial.

DC (Direct Current) in buildings has long been a “yeah but” technology. DC is clearly superior for the home and office. Almost all modern equipment is already DC. We all convert power from AC (Alternating Current) to DC again and again in our homes and offices. Every frustratingly unique power cord, every rectangular wall wart with its glowing green eye is a transformer producing DC power.

Larger appliances, such as televisions and computers, perform the same conversion. The transformers in these devices are hidden inside the cabinet, but the process is the same. There are some exceptions, such as the washer and refrigerator, but certain characteristics of DC motors might push them in to DC in time; already their control consoles are moving to DC. Surely, we already live in DC homes and work in DC offices.

This plethora of AC/DC transformers is a problem. It is easy to get them lost or confused. Each manufacturer selects a transformer as cheap as he can get away with; power, too much power, is lost in every one. That lost power is released in the home and office as heat. In the worst cases, the power used is too much the same whether the device is on, off, or even detached. These transformers have become a significant part of the power use in every building.

If power in buildings was distributed by DC, all these transformers could be eliminated. Better, more efficient, building-scale transformers would convert power from AC to DC more efficiently. Even efficient transformation from DC to AC loses energy, and that energy is lost as heat. In a building-scale transformer, all that heat would be concentrated in one location. In one collection it can be captured and recycled for new use.

Zero net energy buildings come closer fast if we have DC buildings. Solar, wind, and other local power generation technologies produce DC power. Today, that DC power is subject to an AC tax. All DC power must be converted to AC, distributed, and then converted back to DC. This tax may consume as much as 30% of the power available. Even batteries, which store DC power, are subject to this tax. Without the AC tax, every battery that loses just too much energy during storage, is now effectively 30% better without waiting for new technology.

Yeah but...

But buildings are wired for AC. Everything I own today plugs into AC. Even if I could afford to re-wire my building, I cannot afford to replace all the equipment inside. Where would a landlord find someone willing to move into such a building? You can’t get there from here.

I have seen technology that changes all that. Technology that is almost a product enables cost effective installation of a hybrid AC/DC power system in the existing office building. The system uses DC to immediately reduce lighting and networking costs. The solution provides a means to reduce the costs of all building systems that rely on networking. The system can make each room in a building more responsive to the tenant. And the tenant can continue to use his existing equipment as the market matures.

It is time to move DC buildings from the category Yeah But to the category Usable. Migration from AC to DC in commercial space will soon be simple, cost effective, and uncontroversial.

I have been reading through the current draft of the OpenADR standard this week. The ADR stands for Automated Demand Response (although I would prefer autonomous demand response, as regular readers might guess). Demand-Response refers to the conversations between electrical utilities and their customers, so that when the former anticipates a too large demand, the latter might respond with a curtailment plan. This curtailment might be under an existing rate agreement or subject to a live auction.

OpenADR is a nice and well rounded specification, focused tightly on solving today’s problems. Even the documentation, generated using LiquidXML Studio, is clear, crisp, and visually attractive. I wish it were more focused on emerging markets, because the work within it can clearly help them to develop.

OpenADR today has three components: communications between utilities, communications from the utility to the consumer, and communications from the consumer back to the utility. Utilities can exchange information on how much power they can produce. Utilities can alert customers to anticipated shortages and request bids to meet anticipated shortages. Customers can respond by making commitments to shed load, and bidding for the prices they would demand to do so. In the future, the lines between these areas will be blurred, causing the components to blur.

The proper target for OpenADR is the enterprise, not the building. OpenADR and its predecessor, DRAS, started out as interactions with building systems. The proper focus of DR requests is the enterprise. The enterprise owns the building systems and so can decide which requests are worth responding too. The enterprise also owns the business processes, which can enable still greater response than can the building systems. If we do this right, these negotiations will be two-way, creating non-hierarchical markets.

So what do I think the emerging market of the future looks like? How is this market different from the simple interactions in today’s ADR?

Participants will want to schedule things further out. Today’s long range DR is essentially a guess based upon tomorrow’s weather report. Longer term options will be based upon longer horizons. What price can I get if I commit today to a maximum use in the afternoon for Thursday and Friday for the rest of the summer? If I opt for four ten hour days during the summer, will the grid pay more for me to turn off the building on Mondays or Fridays? Building Resources such as conference rooms will know that they are unable to provide conditioned space on these days. Scheduling questions should look more like the corporate standard ICAL (used for scheduling meetings) and less like any control system interval.

What if I am a third party energy manager. I have an ever changing portfolio of customers/office buildings. Because the grid is a physical distribution system, shortages have a defined geographical range. Some of my portfolio will be inside the DR area, some will not. I might wish to shut off some systems in each facility for 10 minutes and meet my bids in aggregate. Every Demand request will include geographical areas following open standards that can be reviewed on any tool I use, even Google Earth.

What if I follow the French model and have an all company vacation during the heat wave. Can I get bids in advance to run my generators during afternoons and sell lit back to the grid? What about my solar cells on the roof for all day re-sale? In the future, every building is potentially an energy source, so every building is a potential participant in as a power seller.

Then there are the questions, the questions that must be answered whether or not there is any current DR event. What is my current use? What is my current price? If I needed more power, what would it cost me? Would the reliability of my portion of the grid be reduced by that request? How much more power can I ask for?

I will write more about this later. But watch for OpenADR.