Transitioning from Fossil Fuels to Renewable Energy
There can be little argument that we will ultimately transition from fossil fuels to green energy sources. It is not a question of "if," but "when" and "how." We can make the transition haphazardly or elegantly. We can make it expensive or affordable. We can accomplish the goal painfully slow or astonishingly fast. In the process, we can continue to enrich corporations, or we can empower individuals and set them free.
Green Energy in New Construction
I remember touring the home of an alternative energy "expert." It was fascinating to look at all his gizmos. He had several different solar and wind systems, plus extensive battery packs, a solar water heater, and a boiler system in his garage that piped hot water into the house. There were wires and pipes everywhere. As an installer, it made sense that he would explore products from multiple companies in order to recommend the best technologies to his customers. But I couldn't help notice the numerous inefficiencies. His house was a modular, factory-made unit - not a particularly energy efficient structure - dropped down on a windswept prairie where it would be frigid all winter and baked all summer. It was of typical, flimsy design; from the fake siding that would get blasted by the wind and rain to bathrooms that would rot out over time to asphalt shingles that would eventually blow right off the roof. And then there were these gadgets - alternative technologies that were insanely expensive and way too complicated, with scores of delicate pumps and sensors and motors. The whole place was a great experiment in entropy - a test of technology against the decaying forces of time. It is a game that time always wins.
The most cost effective, elegant way to go green is to integrate green design into the original plan for the house. A well designed house is inherently efficient and built to stay that way. It doesn't have to cost more in materials; it just requires more thoughtful design, such as orienting the building to take advantage of solar gain with more windows on the south side and few or none on the north side. A furnace should not be necessary, as it only deepens our dependency on fossil fuels and makes the ultimate transition that much more difficult. A properly built house theoretically needs little or no backup heat, although it is nice to have the option of a fireplace or other backup heat to snuggle up to on a frigid day, as detailed in my book Living Homes: Stone Masonry, Log, and Strawbale Construction.
Through hands-on experience, trial and error, and reflection, I have had plenty of opportunity to see what works and what doesn't. For example, in our house, we have pipes running through the wood stove to heat water, which thermosiphons to a storage tank behind the stove. Water heats up and expands inside the pipes, becoming lighter per volume, which makes it rise up through the pipes back to the tank, pulling cold water in to take its place. This thermosiphoning effect negates the need for a pump or thermostat, so the entire system cost only $70 for plumbing and a secondhand storage tank, yet has generated at least $10,000 worth of hot water for free over nearly thirty years.
On the downside, we did not plan a solar water heater into the original design of the house, so we had to build it as a separate unit out in the yard, requiring a pump, thermostat, heat exchanger, and antifreeze to keep the system from freezing. It is so far from the faucets that much of the heat value is lost from water in the pipes after a faucet is turned off. Although inefficient, it too has paid for itself many times over. A solar water heater is best integrated into the original design of a house to make it seamlessly blend in, while potentially avoiding the need for the expensive pump, thermostat, and heat exchanger system.
Given that our house was already reasonably energy efficient, with an electric bill of about $25/month in the 1990s, the cost of installing photovoltaic panels to produce all of our electricity from sunlight wasn't out of reach. Aided by a residential solar demonstration grant to offset some of the expense, we installed a 2.5 kilowatt solar electric system in the fall of 2002.
It is a grid-tied system, in which the meter turns backwards when we produce surplus electricity. It turns forwards at night or in cloudy weather when we cannot produce enough. Over the course of a year, we produce as much electricity as we consume, so that we pay only about a $5/month meter fee, and nothing for electricity. After all these years, it is still a thrill to get the monthly bill in the mail. I never get tired of seeing that our net electric usage is zero. The money that we save each month is ours to spend any other way we see fit.
Integrated design is the most elegant, cost-effective way to build houses that need little or no supplementary energy, but unfortunately, it is challenging to legislate sensible architecture. Requiring a higher r-value for insulation in the walls is a simple and straight-forward solution, but typically makes houses more expensive to build, since the walls are made thicker to accommodate extra insulation. In addition, there is no guarantee that a builder will install the insulation carefully and without gaps, nor that the house will be oriented to take advantage of passive solar gain.
In order to successfully transition from fossil fuels to green energy sources, we must build every new structure to net-zero standards, producing as much energy as it consumes, and we must retrofit essentially every existing structure to a similar standard. To implement this net-zero standard, it would be sensible to set the bar high, educate builders on cost-effective energy efficient architecture, and test the efficiency of each new structure to see if it passes code without remediation. Given a bit of trial and error, builders will innovate their own least-cost solutions to achieve net-zero efficiency.
Retrofitting Older Buildings
It doesn't matter whether a building has stood for a century, a decade, or a day; if it wasn't built efficiently in the first place, then it must be retrofitted afterwards towards the eventual goal of net-zero standards. Achieving such efficiency can be accomplished incrementally and ideally at a profit, with each retrofit more than paying for itself over time in energy savings. Energy conservation typically provides the most cost-effective return on the investment. After implementing optimal conservation practices, then it can be fruitful to evaluate the potential for investing in alternative energy production to offset remaining fossil fuel consumption.
The most obvious energy retrofits are well-publicized already: caulk and weatherstrip around windows and doors to prevent air infiltration, wrap the water heater and hot water pipes with insulation, install better lightbulbs, and add insulation to the attic. For the do-it-yourselfer, these energy retrofits don't have to cost much or anything. In dismantling an old trailerhouse for disposal, I re-used all the fiberglass insulation in the attic of our business at the time, doubling the insulation at zero cost. I constantly find additional new or used fiberglass batts and rigidboard insulation in dumpsters, discarded from other building projects.
Other conservation retrofits may be less obvious, but equally free. For example, I moved our chest freezer from the utility room (next to the clothes dryer), to the unheated workshop, dramatically improving the energy efficiency of an old appliance merely by plugging it in at a better location.
When least-cost conservation upgrades have been implemented, then it is time to consider more extensive renovations, such as installing a solar water heater, adding airlocks at each doorway, or upgrading the windows. For example, a two-inch thick door makes little sense on a house with six- to ten-inch thick walls. And even the most efficient door loosens up over time, becoming a bigger and bigger hole in the house. Adding a well-insulated porch, or some other double-door system, can greatly improve the efficiency of a house. Instead of having two inches of insulated door between the 70F interior and the subzero exterior, you can have double doors with an insulating airspace in between. A double pane window in each door becomes the equivalent of a quadruple-pane window!
The best return on the investment usually comes from retrofits that reduce heating requirements first. For example, window quilts reduce heat loss through inefficient windows. A low-flow showerhead reduces the need for so much hot water. A solar water heater provides hot water without electricity or gas. By retrofitting existing houses with numerous little upgrades like this, it is possible to reduce the energy requirements to the point where it is economical to consider installing solar or wind power to cover the balance.
Motivated do-it-yourselfers can tackle many energy-efficiency retrofits with an astonishingly good return on the investment, saving money on utility bills forever afterwards, which is then free to spend elsewhere. Those who are not so handy can also save big, especially with the aid of grants and tax write-offs, by hiring others to do energy retrofits, such as installing solar water heaters. But it still takes time and awareness to make it happen. Most people are just too dang busy to educate themselves enough to hire someone to come install something as simple as a solar water heater. Therefore, it makes sense to reward public utilities to install and maintain solar water heaters themselves.
It is already common practice that customers can call the utility to inspect and turn on a gas furnace each fall. Why not also employ utilities to install and maintain solar water heaters on every house and business? There is no need to subsidize solar installations at tax-payer expense. Rather, all that is needed is legislation that allows utilities to charge customers for a portion of the energy saved by installing a solar water heater. For example, if a solar water heater shaves $30 off the monthly gas or electric bill, then the customer might keep $10 of that savings, while the utility would bill the customer for the other $20 worth of saved energy - then sell that saved energy to another customer. It is a win-win scenario, where the customer pays nothing for the solar water heater, but gets some of the savings, while the utility fronts the investment, but then gets paid twice for the same energy.
By installing thousands of solar water heaters, utilities can take advantage of economies of scale, obtaining the most reliable technology at the best possible prices to further optimize the return on investment.
Through these kinds of incentives, utilities can profit by helping their own customers reduce their energy demand, rather than by continually building additional power generating capacity. Every house and business can become a green energy provider so that there is no need to build more coal- or nuclear-fired power plants or to bulldoze deserts for solar farms, or to build massive transmission lines to send wind energy from the prairies to the cities.
With or without sensible planning, design, and policy, green energy is coming to America. In particular, the economics of solar technology has consistently followed the same pattern as computers, becoming increasingly powerful at less and less cost. Solar technologies are already in the works that will make it possible to cover every roof with nearly invisible solar electric generating capacity at less cost than we are currently paying for power. Moreover, there are additional products in the pipes that will turn windows into invisible solar panels. Even the paint on your house or car could soon generate electricity. Small-scale distributed energy projects will soon out-produce the multi-megawatt solar, wind, coal, and nuclear power plants that presently provide most of our energy.
The reality is that many new fossil fuel power plants and their transmission lines will never recover their initial investment because the technologies are already obsolete. Unfortunately, the costs of these failed enterprises will be passed along to utility customers anyway. With a little foresight and some sensible policies, we could make the green energy transition a little smoother and a lot less costly.