This blog has
been extremely quiet for two years, mostly because I was busy with other
topics, including Lean and Enterprise
2.0. In my previous post, I mentioned that I was looking at “Smart
Distributed Things” through two instances, Smart Grids and Smart Home
Networks. I will not talk about the second in this blog, since it is
work-related (we’ve come up with the acronym BAHN : Bouygues Autonomous Home
Network).
Smart Grids
make an interesting instance of the “smart distributed network” because of the
extraordinary amount of interest/excitement/hype that exists around this topic.
There is a range of conflicting opinions, ranging from “this is a straightforward
and marginal improvement of existing networks which are already quite smart” to
“smart grids are the backbone of a new sustainable society, based on communities,
subsidiarity (organic,
multi-scale, resilient organization) and self-aware optimal management of
resources”.
I am not an
expert with any of these topics: electricity, power grids, energy, storage …
but like any citizen, I would like to build my own opinion about the future of
our country and our planet, as far as energy and global warming are concerned. Hence
the idea of a small systemic simulation has emerged during my vacation month
(last month). I tried to assemble a crude model of all the different aspects of
the “smart grid ecosystem” as we may understand it, without too much detail,
just the broad principles. Each aspect is actually quite simple to explain, if
taken in isolation (e.g., anyone may understand why it is smart to couple a
solar panel with local storage). It is the combination of all viewpoints,
together with the huge amount of uncertainty (about the economy, the speed at
which technology will get cheaper, the speed at which behaviors will change,
etc.), which makes this a hard topic.
This is
where I got this insight: I actually have a method for complex embedded models
where half is unknown and the other half is unclear: GTES
(Game-Theoretical Evolutionary Simulation). GTES is the perfect platform to assemble
conflicting views of what a smartgrid should be, conflicting
views about how the actors should behave, and try to generate some sense.
In a word, I am planning to build a “serious game” to have
a closer look at smart grids.
Let me
first clarify what I said about the range of opinions and introduce three views
of the smart grid, which I could label: the “Utility view”, the “Google
view” and the “Japanese view”:
- The
“Utility view” defines a smart grid
as adapting the power network to local
sources (as opposed to a one-way distribution network that goes from few
large GW production units towards millions of consumers), adapting to intermittent production sources (though
storage and favoring flexible production units that can adapt to the power
surges of intermittent sources like solar or wind) and using price incentives
to “shave” demand peaks. This is a “no-brainer” program (“what to do”
is clear), where the major issue is price: most techniques show a cost/benefit
ratio that is worse than current practice. To believe in this approach, you must
believe that new technology prices will go down (e.g., solar, storage), or that electricity prices will go “through
the roof” in the next 20 years, or that global warming fears will drive a
significant price for CO2.
- The
“Google view” defines a smart grid as
a change from a tree structure to a network
structure (centralized to de-centralized), the use of market forces to
create a dynamic and more efficient equilibrium
between supply and demand, and the use
of IT to provide information to all actors, including end consumers. The
importance of signals (pricing and power grid control) is so important in this
view that it is often said that telecom, IT and energy network will merge
(something which I don’t believe for a second – but it shows the spirit of the
importance of “smart” in “smart network”). Calling this the “Google view” is a
friendly reference to “What
Would Google Do” J The
core of this approach is the principle that a significant amount of efficiency
would be obtained with a “hyper fluid market”, made possible through IT
technology.
- The
“Japanese view” is human-centered
instead of being techno-centered. The goal is to change human behavior to adapt
to new challenges (lack of resources, global warming, …). Smart grids are the backbone
of a multi-scale architecture (smart
home, neighborhood, city, region, country) where each level has its own
resources and autonomy, resulting in a system that is more resilient and with
more engagement as a consequence of more responsibilities. Smart grids support
the necessary behavioral transformation through communities and constant feedback. I call this a “Japanese vision” because
I have heard it beautifully explained in Tokyo, but the systemic approach is
common to Asia as a whole. Because active communities are “engaging”, Smart
Grids help get rid of waste (muda in the lean
sense) such as useless transportation, un-necessary usage, etc.
These views
do not necessarily conflict; it is possible to envision the union of all these
ideas. However, as soon as one tries to imagine a convincing deployment
scenario, there are a number of questions that pop to mind. Here are a few
examples:
- What part does local storage play? Can there be a smart grid without
distributed storage? What price hypotheses are necessary to make this
realistic, considering that current energy storage price are too high to
justify large-scale deployment? Even if solar or wind becomes free, having to
store the energy with today’s techniques make this approach uncompetitive (with
today’s parameters, obviously)
- What CO2 price would change
significantly the cost/benefits analysis? Actually, this extends more generally to the pair
energy prices + CO2 price, but CO2 price is especially significant. Because of the
abundance of coal, and because of the increasing availability of new forms of
gaz, CO2 price is, from a naïve point of view, the key factor that could change
the economic analysis of introducing alternative intermittent sources of
energy.
- What is the systemic benefit of
local management,
that is, giving autonomy to local community to handle a part of their energy decisions,
at different scales? This is a “system dynamic” issue, related to the handling
of peaks, shortages and crisis. In a regular mode, there are obvious benefits
to the centralized approach, from economies of scale to averaging pseudo-independent
demand. The “pseudo” is a tiny word but full of consequences: the absence of independence
is what produces complex systems and disasters, from the financial
crisis to industrial
accidents. It is the study of bursts and dynamic scenarios, with feedback
loops, that may show the benefit of a “smart system” with faster
counter-measures and learning abilities.
- What could be the large-scale effect
of dynamic pricing on self-optimization of customer demand? The “marginal story” of “peak demand shaving”
is beautiful: to remove the few hours of peak-production with gaz/oil turbines
which produce CO2 at a high marginal cost, by returning some of the value to the
consumer, to convince her/him to postpone parts of her usage. The most common
example being heating (house or water) since inertia makes postponing a viable
alternative. However the story does not necessarily scale so well, nor does it
necessarily address the “resilience issue”. If additional capacity is needed no
matter what to cope with some kinds of peaks, its marginal cost for dealing
with the “other types” become quite small. We are back to a “system dynamic
issue” that cannot be resolved with a “back-of-the-envelope” ROI computation,
but requires a large-scale simulation.
My goal is
to get a first simple set of answers to these questions. Obviously, using GTES
is not going to give me a price or a definite answer, but rather a “sense of
how things are interrelated and react as a whole (system)”. Here is a
simplified description of the model that I have built last month:
This
is a “game theory model” with four actors:
(1)
The
regulator (government) which
controls the price of CO2 and may both favor renewable energy (investment
incentive through tax breaks) or regulate them (impose joint storage with new
intermittent sources). The long term goal (what we call a strategy in GTES) of the regulator is to reduce CO2 while
maintaining the economic output of the country.
(2)
The
utility (national energy supplier)
which runs its production assets, distribute electricity and sets its price
dynamically according to demand and primary energy (oil / gaz) price
variations. One will notice that I implement an ideal world where price can be
set up freely and change constantly, which is very far from the truth, but I
want to address question #4. The long term goal of the utility is to make
money, deliver a proper return on investment for its new acquisition (if any)
and ensure resilience (the ability to serve the necessary amount of energy in
the future).
(3)
The
local operator who operates a smart
grid associated to a city or a county. The operator manages all local
production and storage capacity that is linked to the grid (wind turbines,
solar panels, storage, etc.). It also operates a fossil fuel small-scale plant
to provide additional electricity when required, although it may also buy it at
wholesale prices from the utility. The long term goal of the operator is simply
to make money :)
(4)
The
end consumer who tries to reduce her
electricity bill (both its average value and its expected maximum value) while
preserving her comfort. Optionally, this may mean to reduce her CO2 emissions :)
-
The smart grid architecture is pretty naïve. I simulate a country that could be
France or another European country, with one electricity utility, one thousand
smart cities/ smart communities (with their own local operator), and twenty
millions households. The national supplier produces most of the electricity
when the game starts, using a mix of nuclear and fossil plants. The electricity
is either sold to the local operators, or sold directly to the consumers (hence
each operator has a given market share, that is the percentage of households
that get their energy from this alternative supplier).
-
The
heart of the model is the demand generation. Running the model once demand is
established is not difficult, although the operational mode of the operator
requires a careful description, since many choices need to be made (local
production vs. wholesale buying, using energy from storage or storing energy
for future use, etc.). The demand generator is actually crude and starts from a
yearly and a daily pattern, to which a lot of random noise is added. The model
allows both for independent noise (each consumer is different) and dependent
variation (weather variations are shared by everyone in the same city).
-
Each
actor can play his game through a few decisions (what we call its tactic in GTES). The utility most
important decision is its pricing tactic. Prices are defined through a bunch of
linear formulas, the coefficient of which are GTES tactical parameters. For
those who are not familiar with GTES, an evolutionary algorithm (local
optimization) is run to optimize (find the best value) these tactical
parameters. Other decisions from the utility involve further investments in its
production plant. The local operator has
a similar range of choices to make. It needs to define its operational production
mode; it also needs to set up its pricing scheme. Once a year, it needs to
decide about new investments, whether they are additional fossil fuel production
capacities, renewable energy investment or additional storage. The end consumer
can decide to reduce her demand when the price gets too high, at the expense of
comfort (the tradeoff between the two being a design parameter of the model).
The consumer may also switch from national to local providers and back. Last,
the consumer may invest in “negawatt equipment” (such as house insulation or
more energy-efficient equipment).
This whole
model defines a “game”, which could actually be turned into a real game,
SIM-style. Each actor is trying to maximize its long-term goal while making the
proper “tactical choices”.
What are
the next steps ?
- The
code was written last month but I still need to run “20 years simulations” and
make sure that the model is credible (the story told by one simulation run
makes sense)
- I
then need to “explore the tactics”, which means that when one of the actor make
a decision, the impact on the game outcome is credible. This is the most
time-consuming part, even with a simple model like this. This ensures that the
game is “realistic”, even if it is obviously naïve.
- Apply
game theory to find (Nash) equilibriums –
This is the fun part, since I have nothing to do and will leverage code
that I have written for other problems. This is what GTES is designed for:
looking at the conflicting strategies of the different actors.
- The
last step of GTES is to randomize the “design parameters”. The model relies on
a number of design parameters such as the demand-generation curve, the
sensitivity to price or the efficiency of peak shaving, to name a few. I have
no way to calibrate the S-curves that I am using, so I randomize the choice of
these design parameters (Monte-Carlo simulation)
to see if their value changes the conclusion that I would like to draw from
these repeated simulations.
I’ll post a
summary of my results if and when the computational experiments are successful.
Today’s goal was just to share my overall analysis of the “smart grids” domain.