Frequently Asked Questions by Pouwel Gelderloos, Builder, Oasis Hybrid Homes
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Pouwel Gelderloos

by Pouwel Gelderloos
































Dear Subscribers of the Oasis Hybrid Happenings Newsletter,

     Almost everyone visiting the Oasis Hybrid Home will at some time during the tour ask the question: “When will all these extra expenses, made for the renewable systems, pay off?”

     This is obviously a very important question and I think there is the need to explore the full depth of it, since there are a few different ways to look at the issue and respective answers, depending on the reason why these systems are installed in the home in the first place.

     The main three motivators for people to spend dollars on alternative power, water and heat are:

    1. Not liking the numbers on their monthly utility bills and fearing that the prices
      will run out of control in the future.
    2. Not liking the unreliability of their utility service (storms and other natural disasters
      that affect their general area, but not their house, and create outages)
    3. Genuine concern with the state of our environment.
    4. Any combination of the above reasons.

The answer to the question asked above is different for each of these motives:

      * We are just coming out of the cold winter months and the hurt in the wallet is felt by many as they cope with heating bills, on top of economic hardship. When does it pay off to have an alternative power, heat and water system (from a personal economic perspective)?

     My son, Henry, who helped me build the Oasis House was really envious when his electric bill came in and showed that he used $252 in electricity for the month of February. His well-insulated new apartment has a wood stove for heat, along with energy efficient silicone filled electric base board and measures about 1500 square feet. The Oasis Hybrid Home, where I live, is twice that size and the electric bill was $53.

     The other difference between both houses is that Henry lives there with his wife and was watching his electrical consumption carefully, while I live at the Oasis with my wife and three children and was not watching the electrical consumption too much.

     We live in an area of Montana, where the electricity is supplied by a non-profit co-op that gives us really good rates and we do not get charged separately for water and sewage.

     If I were to assume that Henry lived in a house twice the size of his current one (more equal to the size of the Oasis Hybrid Home) his bill would consequently be twice the amount he currently pays. If he were to install all the Oasis Hybrid energy savers, Henry would save $ 399 -- for this month on electricity alone!

     However, if we were living in the closest town, Henry’s bill could have been much more, since the price per kilowatt is higher provided by a for-profit utility company. Additionally, Henry would have been charged an estimated $40 -- for water.

     Living in town, an Oasis Hybrid Home could save, anywhere between $450 to $ 600 during one cold Montana winter month, for a regular 3,000 square foot house.

     Using these some what modest premises, the following calculations can be made:

     Saving $ 450 per month times 120 months (ten years) is $54,000. Realistically you could omit any other loans that costs you $450 a month and put the interest portion charged for that loan also in your pocket. Another way to look at this -- you could take out a loan for that value and install a renewable system and be even after ten years! Also, you would be acting responsibly towards the environment, your family and yourself!

     Of course these calculations do not account for any increase in utility prices which undoubtedly will happen!  In places where the costs of utilities are higher, the pay back period is even shorter.

     In warmer climates the temperature of stored underground rainwater can be used for cooling and also provide a major saving.

     The reasoning above clearly only takes monetary savings into account. But what about personal savings or losses being tallied up when one deals with a natural disaster or a power black-out?

     I am bringing this up because of the ice-storm power outage that happened just before Christmas on the east coast and put 4.6 million people out of power for weeks. Aside from the inconvenience of having to warm your hands on a burn barrel and having to fix your frozen pipes later -- how does that tally and what price would you assign for this?

     The reliability of the power grid and other utilities brings us to the second motivation for having alternatives. Being totally depending on overhead power lines is equal to signing up for a minor and major disaster to happen at any time -- risking your personal and family’s assets and comfort. Insurance companies now have the option for terrorist coverage (in the rare case your personal home would be effected) -- yet most insurance companies find a way to get around paying off victims of common natural climatic occurrences. It is really amazing to me that utility companies are not required to provide and guarantee more reliable power -- to the degree where their systems are impervious to common, seasonal climatic extremes. I see investing in the Oasis Hybrid Home concepts for your personal home not only as an immediate money saver, but also as a must-have family insurance policy!

     *The idealists amongst us that take personal responsibility for situations and conditions we are facing in our society and the environment today.

     They can see that the environment is heading for a similar crash as the economy is now experiencing (like an oil tanker heading for the docks where, by the time the captain wakes up, it is too late to avoid a head-on collision). There is no doubt in their minds that any action they take immediately results in a payback (even in a small way) by putting the breaks on that oncoming crash.

     Really, when you think about it, there is no dollar amount that can truth fully represent the value of keeping the environment habitable for future generations.

     This is the best and highest motive for doing my part in reducing my carbon footprint and any other type of pollution that effects our environment. This falls in line with the new and “enlightened” economic thinking that, besides personal benefit, includes the cost to the environment and society as an equal or even more important factor in the personal decision making process.

     Quite frankly, it is just as unrealistic to exclude from our personal decision making, the cost of those decisions to the environment and society, as it is to ignore the effect of short sighted monetary profiteering and politics, which is the cause of our economic despair now!

     Unfortunately, we as a society, still see many in high places suffering from a serious case of tunnel vision. We, though, at the grassroots level, can start the healing with individual acts of responsibility, to include the interest of all, now and in the future!"

     Thank you for making the time to read these words and becoming a part of the change that we make voluntarily.

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     Although not a frequently asked question, this is one that must be crossing people’s minds when visiting our web site, taking a tour or otherwise becoming acquainted with the Oasis Hybrid Home concepts.

     A gentleman (Mike) from Belgium had the following remarks and question: “I do see the potential of a Hybrid house, because permits will not be as hard to get. However, a house like this AGAIN is for the people with either nice savings or for someone to commit to high mortgage payments. I see the mortgage payments as much as a dependency as being plugged into the grid.”

     I wrote him this reply: "Thank you Mike for your question, you are making an excellent point. It seems that we have to go one way or the other. Some people have money and/or a good job so they can afford a mortgage. Then there are the people that don’t have much money, but may have lots of time to do some of the work themselves. No matter how you look at it -- for most people, you will either need time and money or some of both."

     There are many examples of structures that can be created from low cost materials such as straw bail houses and the earth ship (a house built from used tires and recycled pop cans and bottles). These structures are innovative ways to build, but encounter code issues with local building authorities.

     If you aim to build a home for your family where there are no local building codes, then you could build a house with recycled and used materials. This could be a sensible option. If however you would unexpectedly have to move, you would have a hard time selling your property since banks will not loan money for such a structure. This means you would need to find a cash buyer.

     On the contrary, Oasis Hybrid Homes are equipped with normal conventional utilities and are built with conventional building materials. Because of these facts, they can be financed by banks and sold as regular real estate (with a lot of additional bells and whistles). The conventional grid-tied utilities installed in the Hybrid home are set up to be used as back-up only.

     In other words, the Oasis homes are set up to use the naturally harvested elements first and to only switch over to the conventional grid when those harvested resources run out. All this is done without any interference by the home owner because the mechanical systems are fully automated. By having both systems the Hybrid Home owner and their families can grow into a sustainable lifestyle without limitation and enjoy renewable energy freedom.

     We all know and understand that there are many people who want to change and to help save the environment by being more energy independent. It is possible to live completely off the grid when the owners choose to live more frugally. (It is nice to know that with the conscientious use of water, heat and electricity, one could survive indefinitely without any outside supply in case of emergency or during a family money crunch.)

    If you find this idea hard to impose on your family, the Oasis Hybrid Home concepts will accommodate you by providing a renewable energy system that is seamlessly backed up by the grid.

     Mike, thank you so much for that great question. Please all ye great thinkers, give me another one!!

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I have been asked this great question, which requires and justifies a great long answer:

What, in your opinion, is the most important feature in the Oasis Hybrid Home?

      Without a doubt, all the design that has gone into a self sufficient water supply is the most important feature of the Oasis Hybrid Home design.

      Think about it: Mankind has lived for centuries without electrical power, but never have they lived without clean drinking water!

      Power outages are major disturbances to our daily routines, but when we cannot have access to clean water, we pretty much immediately have to move to where there is a supply.

      I thought this fact was so important, that the effort and expense to develop an independent water supply has outweighed the expense and effort to install independent generation and storage of power.

      The Oasis Hybrid Home collects rainwater from the roof and stores it in tanks buried around the perimeter underneath decks. The capacity is calculated to span the driest periods with conservative usage.

      Here in Montana, where we have about sixteen inches of precipitation per year, we need to collect all we can get, even snow and ice during the winter.

      Our steel roof features a large three foot wide gutter, designed to capture and hold snow. Embedded in this gutter is a solar heated hydronic loop, which is capable of melting snow and ice, and then send it as water to our storage tanks.

      This rain water is filtered before it goes into the storage tanks by a pile of rock and sand placed in the gutters at the entry of each downspout. This prevents debris from entering the tanks.

      We have three 1,600 and two 2,500 gallon storage tanks placed directly under the downspouts. At our location the tanks are topped off with an abundance of fresh spring rain water in May and June.

      The tanks are connected with a pipe that levels the contents at all times. One tank houses the solar powered pump that pressurizes the house. This tank also contains a low level float which talks (by motorized valve) to a well pump and makes it throw some water in the tank, in case of an extended drought.

      Before the captured rain water is allowed to arrive at the house faucets, it is first filtered through a twenty micron filter, then secondarily through a three micron filter and thirdly through a U.V. filter.

      The result is fresh, clean and healthy drinking water delivered to all faucets in the house!

      To be fair and realistic; There is some work involved with owning your independent water supply. In my opinion a small price to pay for being in control of it.

      The chores entail:

  • Cleaning your tanks and gutters once a year. (Preferably late fall after the trees have shed their leaves.)
  • Changing your particle filters every two months in the summer and once every three months in the winter.
  • And having an annual water quality test is a must.

      All that I have said so far relates to how the rain water is collected and then arrives at the faucets. For responsible water usage, there are some features installed throughout the house that are just as essential. The 9800 gallons of water storage capacity would not be nearly enough without the following water saving features.

      This capacity was calculated to be sufficient to span the dry periods here in Montana with conservative and conscientious water usage. We have installed the following systems in the house:

  1. A gray water recycling system, designed to reuse gray water for toilet flushing (water savings 40 %!!). (Note: gray water is all water drained from any fixture, except the toilets.)

  2. A domestic warm water circulating loop eliminates wasting cold water while waiting for the warmer temperature water to arrive at the faucets. (exact savings are unknown, but in the thousands of gallons each year)

  3. Dual flush toilets save one gallon on each # 1 flush.

      None of these features inhibit the luxurious lifestyles we have grown accustomed to, but they do give us the option to be more water use conscious, if we choose to be or have to be because of an emergency.

Next month in the frequently asked questions, I will elaborate more on the water saving features installed in the Oasis Hybrid Home.

Please send me your questions!

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       Today we are publishing another great set of questions to deepen the understanding of why the Oasis Hybrid Home design principles are so perfect for residential and commercial buildings alike! I have thrown a line to a few local businesses to see if they would implement some of these principles in their buildings. I would expect a large draw of customers who will enjoy being the proud owner of the first self-sufficient Bank or grocery store in town! I hope you will enjoy these questions and fire off some more for me to answer!

Does the sparse setting lend more of an opportunity to take the most advantage of natural resources?

       Anyone with an acre or more can build a hybrid home. Many places are suitable for the harvesting of natural elements and house design, but each piece of land has its own advantages and challenges. As part of my business, I plan to consult for people interested in building their own hybrid homes, which will include evaluating their property before they build. I built my hybrid house on a 1.3 acre lot burdened with many easements. We squeezed it in, but I think that anything smaller than one acre would possibly face some limitations to an ultimate design because of nearby structures, trees not your own, covenants and codes. Being within the city limits can present some limiting factors relating to location, local codes etc. But every home, planned or existing, can be fitted to do something to generate and/or save energy and water, whether by installing solar panels or by collecting rain water from the roof for irrigation. Even small changes help in the greater picture of the positive effect on the environment, the increased level of independence from power companies and the money savings from having to fill your propane tank fewer times.

Would a home of this magnitude fare well in a more urban neighborhood?

       Yes, this house in its full-blown version, can be built on any site an acre or larger. Even some smaller sites would work if there are no easements or restricting codes. Again, each site is unique and I would be able to advise those interested in building a hybrid home how to size it and best adapt it to their particular circumstances.

What is an average electricity bill for a month of service?

       We are paying $15 just to be connected to the grid. From May to September we are generating an excess of energy, so $15 is our bill. The remaining months we can also be entirely off the grid if we are conscientious with our energy use. In a grid-tie situation with a for-profit utility company (as opposed to non-profit coops, which is what serves our area) people can cash in on built up energy credits. This is an agreement with the utility company, where people earn credit if they generate an excess of energy and sell it back to the power company. They can then use that credit to supplement their energy needs, say in the winter, when they typically generate less solar electric power.

What is an average water bill for a month of service?

       We have a water collecting capacity of 10,000 gallons which is enough to span two dry months. We have no bill for water whatsoever unless we run low and our well pump kicks in to dump some water into our rain collection tank to cover the shortage. Many people don’t realize how important water is. In New Mexico and some of the more arid states, the lack of good water is becoming a real crisis. People have lived for centuries without electricity, but no one lives without water. By collecting and conserving our own water, we can become more independent of this looming crisis. I purify my water with three different filters including a UV ray. We live in a time when so many chemicals, and now even pharmaceutical drugs, are showing up in our drinking supply. I’ve had my water laboratory tested and when it comes out of the faucet, it’s cleaner than our local well water, which is drawn from 300’ below the surface. As an added benefit, I have 10,000 gallons of water constantly present for fire protection.

Compare that please to what it might be if you weren’t equipped to take advantage of the rain like you presently do?

       Hard to say in this location since we do not get billed for water, but our well pump runs on the grid and thus adds to our electric bill when it is used in a rare case. In a city, (Livingston for instance) I would estimate the bill to be $60 a month minimum.

And natural gas, today versus what it might be otherwise?

       Being in a rural area, we use propane rather than natural gas. While I have not done the math yet, we are only using a fraction of what we would otherwise use because we now don’t need gas to heat the house or the hot water. I would estimate that we use no more than 300 gallons of propane a year for cooking and drying clothes. If we chose to do so, the house can easily run without propane or natural gas since it has a large Russian style wood burning stove insert set-up for barbeque and cooking. The attached atrium, besides being a passive-solar-heat generator and gray-water recycling plant and food-producing greenhouse, also makes an ideal place for drying clothes.

Describe a major challenge in the day to day operation of the home. How is it overcome?

       There are none that we have encountered so far. That’s the beauty of this house—that it will allow mainstream America the ability to live in harmony with nature without compromising the comforts and conveniences of a modern lifestyle.

Would a home like this be manageable for the average homeowner? How would a homeowner educate themselves to be effective in the management of a home like this?

       This home would definitely be manageable for the average homeowner. A complete operation and maintenance manual comes standard with the house. Besides changing the filters on the fresh and gray water systems and an annual check of your windmill, the Oasis Hybrid Home requires no more looking after than any other house. Just observe in awe and see how Mother Nature’s free gifts can work for you.

Do you think there is more ‘work’ (as in attention) that needs to be paid in the upkeep (as in the harvesting) of the home?

       As I said above, beside changing a couple of filters and checking the windmill once a year, there is no more work than any other house. At the same time, there is natural shifting of ownership of the power supply from the utility companies to the home owner, just as ownership of transportation shifts when we buy our own car as opposed to relying on public transportation. This shift of “energy consumption” from the public domain into our own hands allows us personal control over our bills, the quality and consistency in delivering those utilities, along with empowering ourselves to personally contribute to a “green” planet. All systems in the house are constructed with regular off the shelf materials. That fact, along with an extensive operation and maintenance manual, makes the house simple to work on.

What is the ballpark-price of a home like this to the homeowner buying today?

       This home will cost about $175 a square foot, about 30 percent more than the typical home. Depending on choice of finishes and interior design it could be more. But with rising energy prices, the payback for the initial investment is becoming more and more attractive. And it’s hard to put a price on the peace of mind from blackouts, brownouts, water shortages and so on, not to mention the satisfaction of living in harmony with the environment. This house is good for the soul.

Are more planned in the future? Do you plan to build more?

       Yes, since these design concepts are creating a new focus on the use of natural elements in building, we will build more for clients in sizes and designs according to their desires.  We also have for purchase on our web site a full set of plans for people to do it themselves, utilizing some or all of our energy-saving systems.  People interested in only the gray water system for example, can buy the sheets only pertaining to that portion of the design.  These designs and concepts can also be adapted and modified to existing homes in most cases.  Of course the most optimal application of the design is to start from the ground up, keeping these concepts in mind when selecting a building site.  

       Our company also provides a complete consulting service.   We can help people starting with a free orientation phone call to determine feasibility, and continue with them all the way to managing their project on energy efficiency and working with them, their architects and builders.  We are planning to produce instructive DVD’s and literature to be available as well. People can order any of these these items and stay informed by frequently visiting our web site:

In your opinion, what is the home’s most attractive feature - what are you most proud of, whether efficiently or aesthetically or financially or environmentally? Describe your biggest reward.

       I’m most proud of the complete design. I’m very excited that I was able to realize my vision and build a house that is energy independent, aesthetically beautiful, environmentally friendly and financially sound for both bank loans and as a solid investment. Besides that, if I had to choose my favorite feature within the house, while it would be very hard to do since there are so many, it would probably be the atrium or solar room. This room adds a special ambiance to the adjoining living room…who doesn’t love to walk right into a green house from your living room? Besides being pretty, it is a passive solar “heat generator and battery” providing all necessary heat for the house. In addition, the atrium grows food and is a biological gray water recycling and heat reclamation plant. That is an awesome deal.

What has this home given you back personally?      

       Building the Hybrid home has given me the opportunity to express my creativity and that is a personal satisfying endeavor. Just being able to apply myself to the right project is fascinating and fulfilling! The home is a delight to live in; warm, yet open, almost blending with the outdoors. I get to meet many wonderful people touring the home and recognize that anyone visiting is resonating with the concepts embedded in the house, because this is the natural harmonizing way to build. It is a great feeling to know that I have taken back my independence from the energy companies and their monthly bills and have done something positive for the environment in a big way, including reducing greenhouse gases and my own carbon footprint.

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       Thanks to the article in the USA Weekend magazine and the mention of our web site, all of us are now an Oasis 'online community'!!!

       I hope to talk with you about many exiting topics that represent new ways of thinking and consequently will effect how we might live more in harmony with nature using her ways.

       I am not talking about biology class or a nature walk, but about observing what works and how we can copy what nature already has established as the solution to a problem!

       First, I think you have the right to know who I am and why you would benefit by reading this newsletter. The following questions and answers were selected for this purpose.

Where did the initial inspiration come from for you to build a hybrid home?

       In all truth, I was ready for a new adventure, but let me tell you why I picked this adventure!

       I have been a builder for 35 years in both the Netherlands and the U.S.A, I have build small and enormous houses, several banks, a factory, a church, a bridge and even a fallout shelter. With all that construction, there was always something missing….

       I was realizing that creatures in nature make use of natural elements for their shelter and comfort. When you watch your dog during a hot summer day, you might see him dig a hole to take advantage of more constant soil temperature below the surface. A reptile lies sunbathing on a rock, using the rock’s thermal mass to enjoy the heat more evenly and for a longer time. All animals will quench their thirst at a place where the water naturally collects.

       We, as the smartest animal though, have plainly thought and worked ourselves right out of using those free natural gifts of Mother Nature, when it comes to creating our shelters.

       Very seldom is a structure designed to make use of solar heat gain or to collect the water that falls on the roof without our own effort. We don't collect the sun's and wind’s energy already available to us on our own land, which we could use to run all our gizmos.

       Instead, for decades, I, we have been participating in the building of structures that ignore these natural resources. The needed heat, water and power to run these structures, is brought in from far away destinations at a great cost to our environment, pocketbook and independence.

       We are hooked on life support, if you wanted to compare our buildings to a patient in intensive care! What happens when the life lines get cut? The patient dies and when the power line goes down or the water stops running, we cannot live in our shelters.

       Experiencing this change in awareness presented great, but welcome, challenges in design and workmanship for a builder (me), bored of following the same old designs.

       As I became aware of these human contradictions to the natural flow and balance in nature, I also became more and more interested in the achievements of some brave pioneers that have ventured into building designs, that are more in harmony with the natural elements.

       Soon I became fascinated and thought that I would like to put a house together, improving upon some of those ideas and using many of them, thinking that this could be the beginning of a paradigm shift in the building industry.

Do you live in the home; is it your primary residence, or solely a tourist attraction?

       My family and I are living in this wonderful house and we are having the amazing experience that all the systems and design features are working flawlessly. We are not set up as a tourist attraction, but we have given free tours every first Sunday afternoon of the month. (Contact us for that by e-mail, if interested)

Why Montana?

       Being born in the Netherlands and having lived on that very flat piece of land (measuring four times the size of Yellowstone Park) with sixteen million fellow Dutchmen eventually put a bit of a damper on my creative urges. I liked the tulips though!

       Before my wife and I had our children, we traveled in Asia and were particularly fascinated with the Himalayas. The valley nestled in the Rocky Mountains, where we live now, is called 'Paradise valley' for a very good reason. Seeing such majestic mountains daily continually reminds me that something greater created the human mind. Looking at any part of nature should do that, but beautiful mountains, a roaring ocean or a starry sky really impress that idea in a deep way. To me it is important to daily connect with that beauty.

       Next month around this date, I will go more into the 'meat and potatoes' of the Oasis Hybrid Home. Please send me your questions and comments.

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QUESTION -- Can an existing house be retrofitted with the Oasis Hybrid Home concepts?

       Hybrid concepts will perform best when designing and building a house from scratch. You can use these ideas to retro fit almost any house. For example: All houses have at least one side facing south. The addition of a window and some thermal mass in one or another form, can help with your heat bills. You may consider adding an attached green house for this same purpose and you will enjoy the extra ambiance that provides.

       Every house has a roof that can be used for rain water collection, even just to irrigate your plants around the house!

Oasis Hybrid Happenings

       In upcoming issues, Pouwel will access his 30+ years of experience to answer questions that concern our readers. We encourage you to E-Mail your questions now.


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