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Who we are

Although Vahid Biogas was established in 2008, its principal, David William House, has been a consultant for more than a decade, and is widely experienced in several fields.

David William House

  • Author of Methane Systems, The Complete Biogas Handbook, Journey (a book of poetry), and co-author of Wind & Windspinners
  • Has lectured in more than 20 countries worldwide, and currently facilitating workshops about small-scale biogas production and use.
  • Established earthmind, a 501(c)(3) non-profit organization pursuing research and offering information about ecological living
  • Created Computer Classroom, a computer training company
  • Founded ici, a computer hardware and software sales company
  • As a computer management consultant working primarily along the West coast of the US, developed internal training systems and company-wide standards for clients, programmed a custom application for the US government, and solved problems for some of the largest businesses in the Northwest
    • An internal audit of one company which had been a long-term client found that the company had saved several hundred thousand dollars as a result of innovations in its processes introduced through his consulting services
  • As CEO, ran a medical device company (successfully sold in 2007)
    • Re-established the company's manufacturing system, improved quality and reduced the cost of manufacture of the company’s primary device by more than 70%
    • Published in an international journal regarding tinnitus
    • Awarded a patent (USPTO 7,266,209; or see Google’s version) for a new technology (ultrasonic electrical stimulus) relating to cochlear implants
  • Featured Columnist for Renewable Energy World (see this article about the Clean Development Mechanism, or this article about a few of the virtues of biogas.)

What we do

Recent projects:

  • The Internet potentially gives all of us a global reach:
    • India: We were asked to review a jatropa plantation for biodiesel. Could the resulting glycerol and seedcake be used to generate biogas? We answered the question, and demonstrated that the proposed yield figures for the project were high by 200%.
    • Singapore: We designed a portable substrate test unit and a complete test protocol for a client interested in evaluating opportunities among the islands of the western Pacific.
    • Hawaii: We are working on the design of a digester for an aquaponics farm, and assisting in the development of a biogas lab.

We help create new opportunities:

  • New carbon awareness:
    • Voluntary, compliance, CDM, Gold Standard, tCO2eq, NRB studies: We can help you navigate the new carbon markets at the needed level of detail.
    • Carbon neutral? Carbon negative? In this complex new era of carbon footprints, we can help you get there.
  • Project development:
    • Uncertain of yield, design, sizing, feedstock, siting, economic benefit, financing options, which construction firm to select? We can untangle those knots.
    • Looking at both the business issues and the technology, we can help you focus your strategy, improve your prospectus, and enrich the business plan.
    • We can respond to an opportunity with a robust design for your project.

      (An example? From a report for the portable substrate test unit mentioned above, see this extract, discussing various ways of measuring gas production from small [< 30 liter] portable lab digesters.)

We strengthen the foundation:

  • Project review:
    • Are the core yield assumptions reasonable? Sustainable?
    • Can the proposed design achieve its stated goals?
    • Are there ways to improve or better ways to gain a solid ROI?
    • Are the “hidden assumptions” correct?
    • Does it ‘pencil out’? Do the numbers hold up?

      (For an example of one of our project reviews, see this extract, discussing Jatropha curas yield for a biodiesel project in Chennai, India.)

  • Targeted support:
    • Computers are second nature to us. We can develop or pro­gram­matically extend Excel spreadsheet models of your business and its key aspects, and/or provide you with rich and complex Word documents suited to your purposes.
    • Are there some facts that are missing, or positions that are not fully supported? With short-term, well-focused assistance, we can provide you with good data, clearer insight and improvements to the triple bottom line.

Surprise us:

  • Out of the box:
    • Consulting has its own ethic, and we believe in being trustworthy and achieving excellence. When they have gained experience with us, our clients have often taken us by surprise with requests to solve unusual problems or address unique challenges. What’s yours?


  • As a result of a strong connection with a very large NGO in Sri Lanka serving 15,000 villages, we are working on establishing thousands of small biogas digesters in that country, to be paid for via CDM, resulting in:
    • very significant health and quality-of-life improvements for villagers (particularly women) allowing more robust educational opportunities and other benefits;
    • a reduced environmental impact; and
    • an on-going supply of carbon credits (CERs) suitable for sale in the compliance markets; which may offer
    • a solid ROI for funders.
  • We are seeking contact with those who wish to do well by doing good. Are you one or do you know someone who might be? Please