Energy Efficiency, Killing Us Softly

St. Patrick's day reminded me that it is high time we learn to tell the real green from the fake stuff, beginning with energy efficiency, which has been unjustly conflated with sustainability, when in fact it does the opposite: it increases carbon emissions over time, except at a slower rate. It's high time the FTC should start taking on green washing, beginning with such seriously misleading names as the ConEdison Greenteam. The fact is that, when energy efficiency is pursued without further qualification, and it is applied to systems that are 95% driven by fossil fuels, we are shooting ourselves in the foot with a bazooka. Making a bad system better will solve nothing, except making fossil fuels viable longer, instead of finding a real solution. The fact is, efficiency applies equally to fossil fuel-based systems or renewable energy systems, but only renewable energy systems can reduce GHG-emissions. So we are reminded once again, that it does not pay to major in a minor, or, in the words of the incomparable computer scientist Donald Knuth:

Premature optimization is the root of all evil.

Here is the quote from Donald Knuth, discussed in an article, the Fallacy of Premature Optimization. The energy equivalent to this proposition is that:

Premature Energy Efficiency is the best prophylactic against deep energy retrofits. Or, to but it more simply, if you pursue energy efficiency first, without regard to the long term energy plan for a facility, you will incur sunk costs, if nothing else because of diminishing returns.

Let me count the ways

In no particular order, but with some attempt at logical grouping, here come all the reasons, with some links to other posts on this site or other sites where appropriate. A completely logical and progressive ordering is not feasible due to the interdependence of many of the items listed here.

1. The obvious issue is that energy efficiency makes economic sense (to the extent that it is optimal) whether fossil fuel or renewable energy is used. Therefore, it is a secondary objective in an optimal design, not a primary one. The payback for efficiency comes from reduced energy bills in the future in the case of fossil fuels, or reduced capital expenditures in the present in the case of renewable energy (less installed capacity needed). Another way to state this is that energy efficiency does not generate energy: it is not an alternative method to generate energy.
2. Historically, the conflation of energy efficiency with "green" energy or sustainability, goes back to the energy crises of the 1970's. It was then thought, probably correctly, that the marginal dollar spent on reducing demand was more effective than investing it in increasing supply. The concept was enshrined by the thinking of Amory Lovins, who made the confusion complete by treating energy efficiency as the "fifth fuel." This type of thinking resulted in policy making that treats energy efficiency and renewable energy as interchangeable and complementary, or even additive, which most often is not the case, because different decisions would be made about energy efficiency in a fossil fuel infrastructure than in a renewable energy system. In truth, energy efficiency is not even an investment, it's a mere operational savings, and financially it should be treated accordingly. Renewable energy is truly an investment, a make versus buy decision, a permanent price hedge, and it improves building resilience, and adds value to the asset.
3. Then there is the famous Jevons paradox, which in effect states that increased efficiency increases demand, and therefore does no such thing as conserving energy. Jevons was speaking about coal, and by and large his predictions came true, and are equally relevant today about oil and gas.
4. It gets better (or worse, depending on your point of view). Steve Hallett, in The Efficiency Trap, takes his perspective from biological/systems thinking, and notes not only that greater efficiency lowers the cost of the energy input and stimulates demand, but there are often knock-on effects. For example not only did we fly more as flying became more efficient, but we also built more airports, etc. The end result is that energy efficiency "improvements" make the problem worse, not better, and we have plenty of historical examples to show this. At the other end, exploration costs are going up all the time, so that the massive carbon deposits we theoretically still have are becoming less and less economical to exploit (even aside from the GHG-emissions question). In short, energy efficiency keeps carbon energy more economical for a longer period of time, and therefore increases GHG-emissions over time, which is the opposite of what we want. Hallett's conclusion is simply that the road to hell is paved with efficiency. In his words: "Efficiency promises to conserve, but actually consumes. Efficiency is a trap."
5. The Jevons paradox and the efficiency trap are bad enough on a macro level, but on an individual project basis we see that if we do our economics right you cannot save yourself rich: energy efficiency yields diminishing returns whereas renewable energy generated on-site can bring compound returns. The truth quickly becomes evident if proper capital budgeting is done for the energy infrastructure of a building (home). Thus, within a given building retrofit, energy efficiency (of the fossil fuel-based infrastructure) competes against renewable energy. As long as payback of the equipment from marginal savings is used for decisions, energy efficiency will initially always seem to outperform renewable energy, but when 30-year cash flow analysis is used, renewable options often prove more attractive. Compound returns can be achieved from engineering synergies by integrating several technologies.
6. On the margin it is already clear that net-zero building is the healthiest construction sector, and has been so for several decades, regardless of economic cycles, and in downturns these buildings have kept their value better than other buildings. Since in the larger economic sense the rate of change at the margin drives valuation, it should be clear that fossil fuel buildings are going to continue to lose value at an accelerating rate.
7. Therefore, any older buildings worth preserving should switch to renewable energy and attempt to become net-zero or near-zero, and buildings that cannot make the switch to renewable energy will be the slums of the future, and ultimately headed for demolition. Along those lines the current fashion (think NYC Clean Heat) of switching fuels mostly from coal and heavy fuel to natural gas, amounts to capital destruction. The same applies for energy efficiency initiatives such as New York's Local Law 84/87/88: these measures constitute majoring in a minor, and therefore guarantee failure in the form of strongly suboptimal outcomes, including, at the extremes, the preservation of some buildings that should be demolished, and the failure to convert other buildings to renewable energy when they have the potential.
8. A systems approach is needed, and almost all policies and incentives have been targeted at the technology (widgets) level, not the system level. The smallest system, the economic atom of real estate is a single property (house, building), and above that are neighborhoods, towns, cities, regions, states, countries, and eventually the whole world. In some cases regional planning can be very effective, but we should engage everyone from the smallest economic unit of a single property on up. Incentivizing specific technologies leads to market distortions and bad engineering. Solar PPA's are a case in point. At 17% efficiency, Solar PV should be the last choice, as solar thermal is 98% efficient (or arguably more, because process heat is easy to store for intra-day usage, which gives you higher returns than selling your kWh's back to the grid or using expensive chemical batteries).
   Incentives for individual widgets reinforce a bad financial habit of evaluating options based on the payback of the equipment from energy savings, which flies in the face of optimal design on the level of the property as a whole. The Baucus energy tax proposal focuses on overall GHG-reductions, but so far addresses only the supply side of the grid. Clearly, the demand side should be included due to the huge potential for generating energy on-site with renewable energy.
9. Green finance, so-called, has been a mixed bag of various flavors of asset backed lending, justified by the fact that it is theoretically "low risk" because it offers what are deemed to be largely self-liquidating propositions, based on energy savings. This is a complete fallacy, and energy efficiency loans and solar PPAs may be the subprime loan scandal of future years. In many cases it is the ease of finance, ease of installation (solar PV!), and Wall Street greed, fueled by misplaced incentives, which are fleecing property owners of their equity, locking them into a suboptimal solution. They waste their roof space, and borrowing capacity when with the same space, using solar thermal (98% efficient), they could have easily provided complete HVAC, reduced GHG-emissions by over 50% while homes and buildings become much more valuable in the process.
10. Securitization of energy efficiency loan portfolios has already encountered some headwinds, and these issues will only become more evident as analysts learn to understand the absence of a sound economic foundation. The typical 15-25% "energy savings," is easily wiped out by both energy price hikes (the winter of 2014 gave us a taste of that!), and by comparable buildings going the renewable route and eliminating 50-90% of their energy bills, and GHG-emissions. (See #6 above).
11. The combination of technology-level incentives (such as tax incentives based on Energy Star ratings), and decision making based on marginal payback of equipment, and partial solutions, lead to either the wrong decisions from a whole building level, in some cases such that they lock buildings out of other, superior solutions, or else they risk "cherry picking" a whole building solution - which benefits the financiers who want to write "easy loans," but rob the building owners of the potential to add value.
12. Policies which limp on the dueling concepts of Energy Efficiency and Renewable Energy recall the roulette player who puts equal amounts of black and red. Treating Energy Efficiency as an alternative to Renewable Energy, or as a proxy for GHG-reductions ensures policy failure.

New York State Energy Plan

The review period for the 2014 Draft New York State Energy Plan is still open, and I have supplied my comments along the lines indicated here. On the whole, the plan has the laudable objective of 50% GHG-reductions by 2030 and 80% by 2050, but otherwise continues the errors that have ensured past policy failure by including energy efficiency and fuel switching in the options. Both of these options are environmentally counterproductive, and ensure minor GHG-reductions in the short term at best, and of course, if we want to achieve the objective of 50% GHG-reduction by 2030 and 80% by 2050, we should focus only on projects that can achieve over 50% GHG reduction. Therefore, neither fuel switching nor energy efficiency should be in the plan.

Letting the market take care of energy efficiency

There is huge potential for renewable energy retrofits that can produce 50% or better GHG-reductions right away, and more later, and in ways that make economic sense today, if property owners make use of the right decision-making models. The EPA provides the Energy Star Portfolio Manager to assess projects on a whole building basis, and the resulting models should be evaluated based on a 30-year CAPM cash flow analysis. This will quickly show that many renewable options that seemed expensive are actually economical based on the long tail of zero energy bills, while the 15-25% "energy savings"  from energy efficiency upgrades will quickly be found wanting, unless some of them can be integrated to directly increase the payoff from renewable energy options.

In short, competitive pressures will become more effective if policies and incentives support renewable energy first, and leave it to fossil fuel companies and their customers to work out arrangements for energy efficiency wherever it is economically justifiable.

Conclusion

We are now experiencing a paradigm shift from the fossil-fuel era to the renewable era, and there is huge potential for quantum improvements, even on a building retrofit basis. The major impediment to GHG-reductions is not technology but proper financial analysis along with incentives and programs that reinforce the wrong decisions. In short, as in any other paradigm change, it is our thinking that gets in the way, but that can be corrected. Once you get it, it's obvious. The 2014 New York State Energy Plan should focus on Renewable Energy, and leave Energy Efficiency to the market.

NYC Energy Efficiency Paralysis - Open Letter to Mayor de Blasio

Energy Efficiency (aka EE) is the most confusing issue in the entire green dialog. It is about time that the FTC took action against anyone claiming that energy efficiency is green all by itself. It depends. If you make a fossil-fuel-based system more efficient, arguably you are reducing GHG-emissions somewhat, but that is seriously deceptive: you are simply extending the competitiveness of fossil-fuels, which is the opposite of what we want to achieve, if reducing GHG-emissions is the objective. If reducing GHG-emissions is what we want, that should be the focus, and Site Derived Renewable Energy (SDRE) is the only real answer.

Most programs nationwide are still stuck in the 1970's energy crisis. At that time, it was thought the issue was simply energy economics, which could be addressed by cleverly realizing that a dollar spent on reducing demand had more of an effect than a dollar spent on increasing supply. The environmental dimension, Green House Gas-emissions was not really on the radar yet. Also, there were not as many building-mounted renewable technologies available as there are today. But efficiency of fossil fuel systems has overstayed its welcome, and is not a major concern for a "green" future. Local Laws 84/87/88 need an overhaul for shifting the focus to SDRE, based on proper capital budgeting for energy infrastructure, not incremental spending on marginal efficiency of fossil fuel-based systems, which leads to capital destruction, not building appreciation--as explained in many ways on this blog.

PlaNYC was a Breakthrough of Sorts

PlaNYC was a breakthrough in beginning to take these issues seriously, but it was heavily compromised by the old efficiency paradigm, and ended up putting marginal energy savings front and center. At some point particulates emissions from #6 and #4 oil became another bad proxy for GHG-reductions. This was merely another diversion from the real issue, and the NYC Clean Heat program was the result, causing a rapid shift to natural gas, resulting in an ominous city-wide dependence on a single fuel. Moreover, by the time of this writing it is accepted wisdom that natural gas is about as polluting as coal, when you add in the losses of methane in production and transportation.

Renewable Energy in NYC under Mayor de Blasio?

We can only hope so. The time has come. I come from the school of hard knocks, having learned as a home owner that I unthinkingly spent myself silly on energy efficiency for two decades, without accomplishing anything. At long last, in recent years I finally began to think about the problem more seriously, and since then the issues have become clear to me. NYC has another chance with another administration. Will we move to the new paradigm? I decided that at the very least I should throw in a suggestion or two in the form of an Open Letter to Mayor Bill de Blasio.

Alternatives to PLaNYC: Pushing Renewable Energy

The open letter to Mayor de Blasio focuses primarily on the NYC Clean Heat program, and the very deleterious spate of natural gas conversions it has brought about. It touches upon the mistaken economics that have driven other elements of PlaNYC, such as Local Law 84 (actually, both LL84 and LL87). These regulations simply push efficiency, and thereby assure the opposite of what they would accomplish: they serve to extend the rule of fossil-fuels with marginal energy savings, and have building owners fritter away capital on incremental improvements, instead of investing it in SDRE.

Energy efficiency is mostly about guilt-free shopping, which is why manufacturers love the Energy Star label, but it does nothing to solve the GHG-emissions problem. Instead, it makes it more intractable by making fossil fuels economical longer. Below I am providing a series of explanatory notes to the Open Letter, some additional comments, and some references that may be helpful.

Notes and References for Open Letter

1. NYC Clean Heat is regressive: By now even the Sierra club is coming back from its advocacy for natural gas over coal (remember Bloomberg donated $50mln for that campaign in 2011?). The evidence is overwhelming that switching to natural gas is regressive for climate change. So converting buildings from #6 and #4 oil to natural gas was a subsidy to the gas industry, and capital destruction for the owners of buildings. SDRE retrofits could have given building values a serious boost, instead of just some small time energy savings at best.
2. The DaBX PlaNYC2020 report was an alternative plan to maximize Site Derived Renewable Energy, and make real reductions in GHG-emissions. We focused on NYC's old line C- and D-class apartment buildings, all in all some 15,000 buildings, a large percentage of which might be able to do such retrofits. We pointed out that these conversions should be done over 5-10 years to maximize the value of existing plant. We emphasized proper capital budgeting techniques to make the right long-term economic decisions.
3. The Urban Green Council later made a more general case with their 90 by 50 report describing generalized solutions across all major building types in the city. The report reinforced the important point that the optimal way of implementing retrofits is over time, by leveraging the economic life-cycle of building energy infrastructure components. Forcing everything to be done at once makes projects uneconomical. The report emphasizes generating renewable energy on site as well, but fails to understand the deleterious economics that result from the focus on marginal energy savings.
4. Geothermal energy is strategically important. It is in fact the single most powerful SDRE option for energy retrofits in NYC. New York's bedrock is an ideal substrate, and with 400% efficiency, nothing beats it: 1 joule of energy in (electrical) yields 4 joule output (heat). At a minimum, buildings can do a Domestic Hot Water solution, but the design needs to be optimized for harvesting of energy, either from time of use metering, or from wind turbines or solar PV. Whenever feasible, it should be part of energy retrofits because of the energy storage capability. In exceptional cases (if there are sufficient grounds), it may be able to provide the total BTU load for buildings. Remember insulation helps too!
5. Solar thermal is a hands down winner at 98% efficiency, and no PV should ever be considered (17% efficiency) if you can do solar thermal at all. The point of generating electricity is that it can be easily transported, but when generating renewable energy on site, you don't have a transportation problem, and retrofitting is becoming easier all the time, although on balance a thermal retrofit is harder than PV. There are many ways conversions can be done towards integrated HVAC even in older buildings, given today's hydronic air handlers, etc. With the forecasts of 3x more 90 degree days in summer by 2050, the time is now to start planning that transition, for buildings that don't offer centralized HVAC will be marked for demolition sooner or later. The old model based on window air conditioners is past its prime.
6. Hydronic heat is more energy efficient. Yet with the NYC Clean Heat program, in most cases, buildings have just switched from oil to gas, and continue to heat with steam. What is needed is a thorough understanding of the economics of conversion to hydronic systems, which in turn ties in with the potential for solar thermal and geothermal. Here is a report from NYSERDA, documenting up to 40% energy savings by switching from steam to hydronic systems.
7. Building mounted wind turbines are coming of age and typically offer more bang for the buck than solar PV, if the building has the right location to use wind energy. Then, there are hybrid solar PV/Thermal (PVT) systems which leverage the best of both solar technologies. In other words, SDRE, Site Derived Renewable Energy, is becoming increasingly realistic for retrofits, especially when considering that in a building you can harvest thermal energy in a variety of ways, as pre-heated hot water from geothermal or as high temperature process heat from solar thermal. All such designs solve the biggest problem of renewables, energy storage. Within a building, bridging the daily cycles does not need to be a problem.
8. Along the fourth dimension: timing is everything. One of the ways NYC Clean Heat is very regressive, is because it once more ignores the factor of time, and aims for a one time conversion for a short-term goal, which moreover now proves elusive, once we realized that the environmental benefit of natural gas is nil. The tie-in of this program with the NYSERDA MPP reinforces that short-term orientation. Long-term building economics dictate that you should generally not replace things before their time. What should be done is long-term planning for an SDRE retrofit, so that at every step of the way, you can pre-engineer the next steps. Both our DaBx PlaNYC2020 and the UGC 90 by 50 report advocate this longitudinal approach, but you need to make the plan first, otherwise you will be designing yourself into a corner.
9. Exemptions from NYC Clean Heat. Once it is understood that far greater advances in the reduction of GHG-emissions are possible with onsite renewable energy, the city should encourage exemptions on that basis, and give buildings 10 or 20 years to comply, provided they start out with a project that yields at least 30-50% reductions in GHG-emissions. Anything above 30% GHG-reductions can generally not be done with energy efficiency alone. The beauty is, that if it's planned right, SDRE will yield superior building economics, and thus increase building values, so that building preservation is ensured with SDRE conversions.
10. Building resiliency is a central point. In the new flood zones, building resilience is mandatory, and in a much more profound way than discussed here. Resilience is a value that ensures buildings can stay at least partially functional in an outage. The switch to natural gas has undermined building resilience in a disastrous way, and it should be reversed as soon as possible.
11. The disaster of becoming overly dependent on natural gas was amply demonstrated in the winter of 2014. Not only were heating bills going up, but more and more electricity is generated with natural gas also, and while january in the past was normally the low season for electrical rates, in 2014 rates were at an all-time high. For my own apartment the ConEdison (spot/variable) rates were ca 7 cents/kWh in 2012, 13 cents in 2013, and 22 cents in 2014.
12. NYC did not have any pipeline ruptures in 2014, as happened in the Midwest. But the city has a very constrained gas distribution system, depending on a few major pipelines, and there are no backup storage facilities (off-shore LNG anyone?). New York production of natural gas is also coming to a stand-still because of environmental concerns.
13. PACE financing is the obvious means that is in place already, and NYC will need it. It is politically a worthwhile project to support as long as it is tied to projects that accomplish at least 30-50% GHG-reductions initially. Once owners have the taste, and make proper long-term capital plans for energy, the potential for building appreciation is enormous. For at every level, if you can generate your own energy on site, that investment in SDRE is a permanent energy price hedge. 50% is really the optimal point to strive for in the initial project, since then the building is "over the hump" with dependence on fossil fuels.

Converting PlaNYC from communism to capitalism

PlaNYC as is, as well as other similar plans everywhere, operate in the central-planning style of the infamous 20 year plans of the former Soviet Union, which were designed to fail, as I've argued here. The mistake is to take the macro view of "energy efficiency" and then ram it down to the micro level with laws and incentives, instead of to engage the economic self-interest of property owners. Property owners should be in the business of maximizing property values, and government- the public interest- should incentivize reductions in GHG-emissions. Energy efficiency is not a proxy for GHG-reductions. Energy efficiency of fossil fuel systems makes GHG-emissions more intractable, so if we subsidize it, we indirectly subsidize the fossil fuel industry.

The energy benchmarking and audits of LL84/87 are a positive. The requirements to tinker with marginal efficiency improvements without totally rethinking the system is regressive, and bad policy. The market might take care of it - or at least need a lot less help than we're spending now on making building owners do things they don't want to do. Net zero construction has been healthier than any other area of construction for many decades, net zero or near zero buildings keep their values better than anything. Once we get building owners to perform serious renewable retrofits, the economics will force others to comply, or die. The simple fact is that with today's technology, 80-90% reductions are possible in many existing buildings, if the buildings follow a deliberate renewable retrofit strategy--the 90 by 50 report from Urban Green Council demonstrates the point. The first project should be in the 30-50% (GHG-reductions) range, and that is more than any energy efficiency project can do. Competitively, the pressure will be on.

Conclusion: Renewable Energy over "Energy Efficiency"

Once more, energy efficiency tends to mean making fossil fuel systems more efficient, and that is not a worthwhile goal for public support. PACE finance is an option that will enable the massive capital investments needed, to facilitate moving energy from liabilities to assets by means of SDRE. The focus needs to shift from energy efficiency of fossil fuel systems to site derived renewable energy and the city can exceed the parameters of PlaNYC completely if it does so.

The Voodoo Economics of Energy Efficiency

Recent reports continue to draw attention to the notion that energy efficiency predicts lower mortgage default rates. Indeed, it seems obvious that energy-efficient homes are worth more, and that mortgage default risk on such properties should be lower. This is the same kind of analysis that was previously used to promote PACE bonds. It may be superficially right, in the sense that the relationship is observable and provable, but it misses the point, simply because a more categorical understanding is possible. Or, while these relationships may exist and seem statistically significant, correlation does not imply causation. There is no consistent approach to underwriting risk for energy efficiency, nor is there an analytically sound approach to explaining why or to what extent the risk of defaulting on home loans is reduced under energy efficiency. The following attempts to fill that gap by means of a simple example.

Energy Efficiency is Secondary

First, energy efficiency is not a primary objective, but a secondary one. The first order of business is a make-or-buy decision about on site generation with renewables (Site Derived Renewable Energy) versus a carbon energy subscription. The easiest way to see this, is to realize that you cannot save yourself rich, something everybody knows and understands. Let's look at four people, property owners all, and their different approaches, Mr. Tinkerer, Ms. Efficiency, and Mr. Analyst, and Ms. Intuition.

Mr. Tinkerer - Energy Efficiency Flying by the Seat of your Pants

• Mr. Tinkerer begins by "saving" energy without thinking, and thereby accepts the status quo. In his single family home he has an $300 electrical bill and an $700 oil bill, for $1,000/month combined.
• He then buys some gadgetry that reduces energy consumption and some insulation, and his bills goes down to $900.
• A year or two later, after some energy price increases, and more wear and tear, he is back to paying $1,000 a month.
• He keeps tinkering and spending money on Energy Star appliances and other energy-efficient products, but never realizes why he's not achieving serious energy efficiency.

This is a case of casually pursuing energy efficiency, and it is probably the most common. Mr. Tinkerer operates from the unexamined belief that he can save himself rich, but all he does is overpay for "energy saving" devices, without ever realizing that energy savings are not additive. Most of us dabble in energy efficiency in similar ways, it's a way to shop without guilt. It probably is a wash in the beginning, we spend as much as we save, but in the long-run we spend way more than we "save." Sometimes it's a lot more, for the savings do not add up, EVER.

Ms. Efficiency - Energy Efficiency by the Book

• Ms. Efficiency really goes hog-wild, and does everything she can to reduce energy consumption, year after year. The first year she spends $3,000 and creates a 20% reduction, i.e. she enjoys a 15 month payback on her investment.
• The second year (she still have 3 months to go to earn back that first investment), she spends $6,000 for a further 10% reduction. Simplistically, 10% of the remaining $800/month energy bill is $80, and therefore she now enjoys a 75 month payback, or 6.25 years.
• The third year she can't find anything else to do, she wants to do something major, and now she talks to SolarCity (or any other similar provider of solar pv on a PPA- or lease-basis), and they can provide her with a solar panel (nothing down!!!) and reduce her electrical bill by 10% (she's already very efficient), for a further 3% of her overall energy bills. It's a 20 year Solar PPA. So now her monthly energy bills are down to $698.40 in constant dollars, but there were a few price increases, so she's at $750/month for the year. However, now her roof is covered with a beautiful shiny solar panel! She sends a Christmas card to her mother, to show off the solar panel, and mom is duly impressed with how green her daughter has become.
• However, once she analyzes the figures correctly, that solar panel is a 20 year investment of $40,000 for a 3% reduction in her energy bills (10% on electricity alone), which means a payback of 154 years.
• She's still paying $750/month in energy bills (including the $200/month solar lease), and the prospects remain that prices will go up for the remaining $550 "energy" portion of her monthly payments. What has she won? To a financier it seemed things have improved, for $750 now is less than $1000 a few years ago, but that PPA commits $40,000 of her borrowing capacity, and the panel locks out most of her roof, for any alternative uses that might prove to offer better results.
• The residual energy portion of her monthly obligations continues to be above 50% of her starting figure.

In short, a categorical make or buy decision has to be made first before anyone starts on efficiency: do we continue to buy energy, or can we economically make our own. On site renewable energy generation is the alternative to buying energy in perpetuity. Energy efficiency only comes into consideration AFTER we make that make or buy decision, or else we falsify that decision, which is now commonly the case.

Energy Efficiency and Diminishing Returns

The example above shows the effects of diminishing returns, the successive investments show less and less savings, because the base is growing smaller. Ms Efficiency started out investing $3,000 with a return of $200/mo then $6,000 with a return of $80/mo, and finally $40,000 with a return of $21.60/mo (clearly she is paying more for every successive improvement, while here additional savings decrease). This is a losing battle, and it is the battle home owners are losing all around the country, as long as they believe in the "savings" paradigm.

Short-term, yes cash flows are improving, but a few energy price hikes can wipe that out, and the result is that eventually the improvements prove minimal or non-existent within a few years.

PACE Bonds and Mortgage Default Risk

The rationale for the creation of PACE bonds was to provide building owners with a means of financing major capital investments up front to do material retrofits in the energy infrastructure of properties. Unfortunately, the PACE bond camp has been hi-jacked by the energy savers also, and thus they have become yet another customer retention program for the energy companies, and the vendors of energy saving widgets, which was not the original idea. PACE bonds were designed to overcome the capital intensity of the switch to renewable energy, not to squander money on energy efficiency enhancements. Investment in renewable energy moves energy from liabilities to assets, and therefore would structurally reduce underwriting risk, if the economics are solid.

Enter Mr. Analyst - Investing in Site Derived Renewable Energy first

Here is how it should work: Mr. Analyst, with the same $1,000/month energy bill, invests significant money (maybe $140,000), and gets 20-year PACE financing that costs him $900/month, but he wipes out 85% of his energy bills. He gets a geothermal heat pump that provides his HVAC, and a solar panel that offsets most of the electrical load. The first year he gets a 30% tax credit on some of that investment, etc., which helps, but he ends up in a similar situation to his neighbor Ms. Efficiency. She went the energy savings route for the first 3-5 years, but then gradually Ms. Efficiency observes her bills nudging above $1,000 again. Mr. Analyst stays steady at $900/mo in payments, and his residual energy bill of $150 grows a little bit, but not a lot. And Mr. Analyst looks better with every passing year. Let's assume that equipment lasts 30 years. By that time the energy profiles of the two homes will be vastly different.

Ms. Intuition - Thinking Long-Term

Ms. Intuition in the meantime may be even smarter, she gets the same geothermal heat pump, and puts it on a time of use meter, running it mostly at night. She reads the papers, and she sees that solar panels today are 15-20% efficient, but there's some new invention every few months that promises a great breakthrough. She waits a few years, until solar panels have gone from 15-20% efficiency to 35% efficiency, and she now installs a solar panel that completely offsets her electrical use, and she ends up with zero energy bills. In short, she "ate" the electricity cost for a few years, but she gained a technology advantage compared to Mr. Analyst. Geothermal heat pumps are already 400% efficient -- returning 4 joules for every 1 joule you supply -- and are not likely to get any better. With solar PV there is another patent announced every week to increase the conversion efficiency, so it was a reasonable guess to expect that the efficiency of that technology would increase in coming years, and that waiting could be prudent. Notice also that the solar panel here enhances the investment in the geothermal heat pump and improves the value of that energy price hedge even further.

These are just examples. The numbers are rough, to show orders of magnitude, but the principles are clear. They show that the passive stance of "energy efficiency" and "energy savings" is often bested by a focus on generating your own energy wherever it is economical.

• We can't save ourselves rich, and energy efficiency might reduce underwriting risk somewhat, but there are better alternatives, such as investing in Site Derived Renewable Energy (SDRE) instead of energy efficiency.
• Energy efficiency is an operational expense, not an investment, it is short term in nature and mostly not part of permanent plant, but subject to wear and tear.
• Energy generation with renewable sources is an investment that adds to property values, by moving energy from liabilities to assets.
• Logically, in the short-term "energy efficiency" might be a self-liquidating proposition, which by definition would reduce the underwriting risk and the chance of mortgage default by the amount cash outflows are reduced, however these effects don't last, for easily provable reasons.
• Site Derived Renewable Energy (SDRE) is a clear and lasting energy price hedge, certainly if more than 50% of the energy requirement can be economically generated on site. In this case the performance of the property improves with every energy price hike, and thus there is a long-term reduction in underwriting risk, and we can expect a commensurate, but lasting reduction in mortgage defaults.
• SDRE also offers protection against a carbon tax, if it ever were to come. Again, energy efficiency cannot do that, even if it may temporarily reduce mortgage default risk. 

Current research into the issues of mortgage default rates fail to distinguish these structurally and financially very different alternative scenarios, while it is analytically clear that the one has a short-term effect, and the other adds lasting value to a property.

Conclusion - Investment in SDRE wins out over Energy Efficiency

Energy efficiency can be shown to produce improved cash flows in the short-run, and therefore should reduce underwriting risk and mortgage defaults. However, for good analytical reasons the longer term value of energy efficiency alone is uncertain, and a better option is renewable energy generated on site (SDRE), that is justified not only by the marginal savings of the equipment, but also by the lasting improvement of property values.