Practical Solar LLC

Practical Solar LLC Long-term thermal storage in pre-existing subterranean geology is hoped to make solar practical ; founded December 2, 2011 by Frank Scruggs

01/18/2026

Rat race
Grok prompt; Help me understand the rat race. By comparing and contrast the opportunities available for the typical rich IE Musk Zuckerberg and Bezos To the median income worker with a mortgage a car loan car insurance house insurance And the typical investments made by each
Thoughts
Understanding the Rat Race
The "rat race" is a metaphor for the relentless, competitive struggle in modern society to achieve financial success and security, often at the expense of personal fulfillment, work-life balance, or long-term well-being. It implies a cycle where individuals work tirelessly to maintain or improve their lifestyle, but external pressures—like debt, inflation, job insecurity, and societal expectations—keep them trapped in a loop, much like a rat running on a wheel without real progress. This concept gained popularity in the mid-20th century and remains relevant today, especially in discussions about income inequality, wealth accumulation, and economic mobility.
To break it down, let's compare and contrast the opportunities and typical investments of ultra-wealthy individuals (e.g., Elon Musk, Mark Zuckerberg, Jeff Bezos) with those of a median-income worker. I'll use the U.S. context since these examples are American, and median household income is around $75,000 as of recent data (adjusted for 2026 estimates). The median worker often has ongoing obligations like a mortgage ($300,000 average), car loan ($20,000), car insurance ($1,500/year), and home insurance ($1,500/year), which can consume 40-60% of their take-home pay.
Key Differences in Opportunities
Ultra-wealthy individuals operate in a fundamentally different ecosystem than median workers. Their wealth provides leverage, scale, and insulation from risks that amplify opportunities exponentially. Here's a comparison:
Aspect Ultra-Rich (e.g., Musk, Zuckerberg, Bezos) Median-Income Worker
Access to Capital Virtually unlimited through personal assets, low-interest loans against stock holdings (e.g., Musk borrowing billions at near-zero rates via Tesla shares), or venture funding. They can fund moonshot projects like SpaceX or Meta's metaverse without personal financial strain. Limited to personal savings, high-interest loans (e.g., 7% mortgage or 10% car loan), or credit cards. Debt service eats into disposable income, making large investments risky or impossible.
Networking and Influence Elite networks including politicians, investors, and industry leaders. Bezos lobbies for Amazon's interests; Zuckerberg influences global policy on data privacy. This opens doors to exclusive deals, like acquiring companies (e.g., Musk buying Twitter/X). Relies on local job markets, LinkedIn, or professional associations. Opportunities are often gated by education, location, or luck—e.g., a promotion at a 9-5 job, but rarely global influence.
Risk Tolerance High, due to diversified wealth. Failures (e.g., Bezos' Fire Phone flop) are absorbed without lifestyle impact. They can pivot quickly, like Musk shifting from PayPal to EVs and space. Low, as risks threaten essentials. A bad investment or job loss could lead to foreclosure or bankruptcy, exacerbated by fixed costs like insurance premiums.
Time and Resources Delegate routine tasks to teams, freeing time for innovation. Access to top advisors, private jets, and global markets (e.g., Zuckerberg's philanthropy via Chan Zuckerberg Initiative). Time consumed by work (40+ hours/week), commuting, and family obligations. Limited resources mean DIY financial planning or basic employer benefits.
Economic Mobility Exponential growth via compounding wealth. Starting from affluence or early success (e.g., Bezos' garage startup backed by family loans), they scale to billions. Tax strategies like stock loans minimize liabilities. Incremental at best. Wage growth lags inflation; mobility often requires side hustles or relocation, but debts anchor them. Many stay in the rat race, saving modestly for retirement.
Barriers to Entry Minimal for new ventures; their name alone attracts talent and capital (e.g., Musk's xAI raising funds effortlessly). High; starting a business means risking savings or taking on more debt, with failure rates ~50% in the first 5 years.
In essence, the ultra-rich escape the rat race by turning it into a game they design—leveraging scale to create asymmetric opportunities. The median worker, however, is often stuck reacting to systemic pressures, with opportunities constrained by immediate survival needs.
Typical Investments
Investments reflect these opportunity gaps. The ultra-rich focus on high-reward, illiquid assets that generate outsized returns, while median workers prioritize stability and liquidity to cover debts and emergencies.
Investment Type Ultra-Rich Examples Median Worker Examples
Stocks/Equities Massive stakes in their own companies (e.g., Musk's ~13% of Tesla, worth billions). They also invest in public markets via hedge funds or direct stakes, often using options/derivatives for leverage. Focus on growth stocks or AI/tech. 401(k) or IRA contributions (e.g., 10-15% of salary), often in index funds like S&P 500 ETFs. Limited to ~$7,000/year in Roth IRAs; employer matches if available.
Real Estate Vast portfolios including commercial properties, luxury homes, or land banks (e.g., Bezos owning hundreds of thousands of acres). Used for tax advantages via depreciation and 1031 exchanges. Primary home as main "investment," but often more liability due to mortgage/insurance. Maybe a rental property if aggressive, but rare due to down payment barriers.
Private Equity/Ventures Heavy in startups and VC funds (e.g., Zuckerberg investing in AI firms; Musk in Neuralink). High risk, but potential 10x+ returns; access via personal networks. Rare; might use platforms like Robinhood for small angel investments, but typically avoid due to capital requirements (e.g., $50k minimums).
Alternative Assets Exotic options like art, yachts, space ventures, or crypto (e.g., Musk's Dogecoin influence). Philanthropic trusts for tax optimization. Basic: high-yield savings (5% APY), CDs, or small crypto holdings. Focus on low-risk to preserve emergency funds (3-6 months' expenses).
Debt Usage Strategic borrowing against assets at low rates to fund investments, avoiding capital gains taxes (e.g., Bezos' "buy, borrow, die" strategy). Consumer debt (car loans at 5-10%, mortgages at 6-7%) that drains wealth; investments secondary after debt payments.
Overall Strategy Aggressive, long-term wealth compounding with global diversification. Annual returns often 20%+ via leverage. Defensive, focused on retirement (e.g., target 15x annual salary by 65). Average returns 7-10% via balanced portfolios, but inflation/debt erodes gains.
The ultra-rich's investments are proactive tools for wealth multiplication, often self-reinforcing (e.g., company stock appreciating from their leadership). For the median worker, investments are reactive—aimed at escaping the rat race through slow accumulation, but hindered by obligations that force conservative choices.
Escaping the Rat Race
While the ultra-rich have largely transcended it, median workers can mitigate it by building passive income (e.g., via index investing or side businesses), reducing debts, or pursuing financial independence (FIRE movement). However, systemic factors like wage stagnation and rising costs make it tougher for the average person. If you're in the median category, tracking net worth monthly and automating savings can help break the cycle incrementally.
What % of the rich income it is available for investment versus the median income at what percent of expected return on investment for each so how long would it take each one to double their money?
Thought for 49s
Percentage of Income Available for Investment
To address this, we need to clarify "income available for investment." This typically refers to the savings rate—the portion of disposable income (after taxes) not spent on consumption and instead saved or invested. For the ultra-rich (e.g., Musk, Zuckerberg, Bezos), "income" is often not traditional salary but includes capital gains, dividends, and business profits, which they largely reinvest. Data is drawn from recent 2025-2026 sources for accuracy.
Median-Income Worker: The average U.S. personal savings rate in 2025 was around 4.5% of disposable income.
finance.yahoo.com +3This accounts for high fixed costs like mortgages, car loans, insurance, and living expenses, which consume most of their ~$60,000 post-tax disposable income from a $75,000 gross household median. Surveys suggest working Americans claim higher rates (e.g., 23%), but official Bureau of Economic Analysis (BEA) data is more reliable and conservative.
nerdwallet.com
Thus, only about 4-5% is typically available for investment after obligations.
Ultra-Rich (e.g., Musk, Zuckerberg, Bezos): For the top 1% (a proxy for billionaires), savings/investment rates are estimated at 40-50% of income.
aol.com
Billionaires often minimize taxable income via strategies like borrowing against assets, allowing near-100% reinvestment of business profits or gains. Their expenses (e.g., luxury but fractional relative to wealth) are negligible, so effectively 90-100% of new "income" (from asset growth) can be funneled back into investments. High-net-worth individuals hold median retirement balances over $1 million, reflecting high reinvestment.
wealthtender.com +1In summary, the median worker has ~5% available, while the ultra-rich have 40-100%, amplifying their wealth compounding.
Expected Return on Investment (ROI)ROI here is the annualized return on invested capital, based on typical portfolios. These are historical averages adjusted for 2025 data; actual returns vary by market conditions.
Median-Income Worker: Typical ROI is 7-10% nominal (before inflation), or about 7% real (after ~3% inflation).
nerdwallet.com +3This assumes a diversified portfolio like S&P 500 index funds via 401(k)s or IRAs. Average investors often underperform the market (e.g., 2-8% due to poor timing), but expected long-term is ~7% real for conservative estimates.
crews.bank +1
Ultra-Rich: They access high-yield options like venture capital (VC) and private equity (PE), with typical ROIs of 15-22% annualized.
azariangrowthagency.com +2Top-quartile VC funds hit 15-27%, while PE averages 13-16%. Billionaires' net worth growth reflects this: Musk's averaged ~40-50% annually in recent years (e.g., $187B gain in 2025 on a ~$432B base, ~43%).
businessinsider.com
Zuckerberg ~35-40% (e.g., $78B gain in 2024).
facebook.com
Bezos ~10-20% (e.g., $24B in one surge).
forbes.com
Overall expected: 15-20% for their riskier, leveraged strategies.
The gap arises because the rich invest in illiquid, high-growth assets unavailable to most.
Time to Double Their Money
Using the Rule of 72 (Years ≈ 72 / ROI %), this calculates how long it takes for invested capital to double via compounding, assuming reinvestment and no withdrawals. We use real ROI to account for inflation.
Group % Available for Investment Expected ROI (Real, Annualized) Time to Double Invested Money
Median-Income Worker ~5% 7% ~10.3 years (72 / 7)
Ultra-Rich 40-100% 15-20% ~3.6-4.8 years (72 / 20 to 72 / 15)
For the median worker, only a small portion compounds, so overall wealth doubles slowly. For the ultra-rich, high availability and ROI create rapid exponential growth—Musk's net worth, for example, has doubled multiple times in under 5 years due to these dynamics.
en.wikipedia.org +1This illustrates how the rat race favors those with scale.



21 web pages
Explain Rule of 72 variations
Tax strategies for billionaires
more concise summary
Grok prompt; In the previous example how long would it take the median income individual to retire with Net worth of $1,000,000
Thought for 29s
Time for Median-Income Individual to Reach $1,000,000 Net WorthBased on the assumptions from the previous example (U.S. median household income of ~$75,000 gross, translating to ~$60,000 disposable after taxes; ~5% available for investment, or ~$3,000 annually; and a 7% real annualized ROI), we can calculate the time required to build a $1,000,000 investment net worth starting from $0. This assumes consistent annual contributions, no withdrawals, and compounding returns—ignoring factors like income growth, inflation beyond the real rate, taxes on gains, or market volatility for simplicity.Calculation MethodThis is a future value of an annuity problem, where regular contributions grow over time. The formula to solve for the number of years ( n ) is:
n=logFV⋅rP1log⁡(1+r)
n = \frac{\log\left(\frac{FV \cdot r}{P} + 1\right)}{\log(1 + r)}
FV=1,000,000FV = 1,000,000
(target net worth)
P=3,000P = 3,000
(annual investment)
r=0.07r = 0.07
(real ROI)
Step-by-step:
Compute the annuity factor:
\frac{FV\cdot r}{P}=\frac{1,000,000\cdot0.07}{3,000}=\frac{70,000}{3,000}=23.333\frac{FV \cdot r}{P} = \frac{1,000,000 \cdot 0.07}{3,000} = \frac{70,000}{3,000} = 23.333
Add 1:
23.333+1=24.33323.333 + 1 = 24.333
Take the natural log (or any base):
\log\funcapply(24.333)\approx3.191\log(24.333) \approx 3.191
Log of growth rate:
\log\funcapply(1.07)\approx0.06766\log(1.07) \approx 0.06766
Divide:
n\approx\frac{3.191}{0.06766}\approx47.18n \approx \frac{3.191}{0.06766} \approx 47.18
years
Thus, it would take approximately 47 years for the median-income individual to reach a $1,000,000 net worth under these conditions. For context, if starting at age 25, this would mean retiring around age 72—highlighting the challenges of the rat race for average earners without higher savings rates or returns. In practice, many aim for 10-15% savings to shorten this timeline, or factor in Social Security/home equity for retirement needs.
What if we refuse to play the game?
Grok prompt; I propose a home construction Co op where the workers live at the prefab site To start When labor exchange Equals approximately $50,000 The Co-op gives them a tiny house 50% of the workers is invested in the Co-op With a 20% expected return per year When their equity reaches 300,000 dollars the Co op exchanges For a typical 1000 square foot Home if this person made the gross income as they did before in the previous example now how long would it take him to retire with $1,000,000 net worth
Thought for 2m 9s
Time for the Individual in the Co-op to Reach $1,000,000 Net Worth
Based on your proposed co-op structure and assuming the same gross annual income of $75,000 as the median worker from previous examples, I'll model the time to reach a $1,000,000 net worth. This is a financial simulation involving annual investments, compounding returns, and the milestones you described (tiny house at $50,000 labor exchange and home exchange at $300,000 equity). Since this is a closed-ended mathematics question, I'll first outline the assumptions, then explain the step-by-step modeling approach, and finally provide the result.
Key Assumptions
Gross income: $75,000 per year (as specified).
Annual investment: 50% of gross income ($37,500) is invested in the co-op each year. (I assume the co-op living arrangement reduces expenses enough to make this feasible, without detailing taxes or living costs, consistent with prior simplifications.)
Return on investment (ROI): 20% annualized on the co-op equity balance (compounded annually).
Labor exchange: Interpreted as cumulative investments into the co-op. When this reaches $50,000, the worker receives a tiny house as a "gift" (adds $50,000 to net worth without deducting from equity, based on the wording "gives them a tiny house").
Equity exchange for home: When co-op equity balance first reaches or exceeds $300,000, it's exchanged for a 1000 square foot home. I assume this means spending $300,000 of equity to acquire a home valued at $300,000 (net zero change to total net worth, but shifts assets from growing equity to a non-appreciating home for simplicity). A "typical" 1000 sq ft home could vary in value by location ($200,000–$400,000), but I tie it to the $300,000 threshold you mentioned.
Net worth composition: Co-op equity (growing at 20%) + tiny house value ($50,000, no growth) + home value ($300,000, no growth). Starts at $0; no debts or other assets included.
Compounding: Contributions are added at the end of each year, with growth applied to the prior balance (standard ordinary annuity: equity = previous_equity * (1 + r) + P).
Other: No inflation adjustment, taxes on returns, or withdrawals. Milestones are checked after each year's growth and contribution. Simulation runs in whole years until net worth ≥ $1,000,000.
These assumptions interpret your proposal conservatively; the homes are perks that add to net worth but don't grow like equity. The exchange doesn't reduce net worth but caps the compounding base temporarily.Step-by-Step Modeling ApproachThis requires a year-by-year simulation (not a simple closed-form formula like the prior annuity) because of the conditional milestones that alter the equity base. Here's how to arrive at the solution:
Initialize variables:
equity = 0 (co-op investment balance)
cum_invest = 0 (cumulative investments)
tiny_value = 0
home_value = 0
year = 0
P = 37500 (annual investment)
r = 0.20 (ROI)
target = 1000000
Loop annually until net worth ≥ target:
Increment year by 1.
Add P to cum_invest.
Update equity = equity * (1 + r) + P.
If cum_invest >= 50000 and no tiny house yet: Set tiny_value = 50000.
If equity >= 300000 and no home yet: Subtract 300000 from equity, set home_value = 300000.
Calculate net_worth = equity + tiny_value + home_value.
Repeat if net worth < target.
Why simulation over formula? The basic time to double or reach a future value uses the Rule of 72 or annuity formula (n = log((FV * r / P) + 1) / log(1 + r)), but milestones interrupt the pure compounding. For reference, without milestones, it would take ~10.1 years (plugging into the formula: log((1000000 * 0.2 / 37500) + 1) / log(1.2) ≈ log(5.333 + 1) / log(1.2) ≈ log(6.333) / 0.07918 ≈ 1.846 / 0.07918 ≈ 10.1). The +$50,000 bonus accelerates slightly, but shifting $300,000 to a 0% asset slows growth, netting a longer timeline.
I implemented this in Python (via the code ex*****on tool) for precision. Here's the year-by-year output for transparency:
Year Annual Investment Equity (After Growth & Contribution) Cumulative Invested Milestone Triggered Net Worth (End of Year)
1 $37,500 $37,500 $37,500 None $37,500
2 $37,500 $82,500 $75,000 Tiny house (+$50,000) $132,500
3 $37,500 $136,500 $112,500 None $186,500
4 $37,500 $201,300 $150,000 None $251,300
5 $37,500 $279,060 $187,500 None $329,060
6 $37,500 $72,372 (after exchanging $300,000) $225,000 Home exchange (+$300,000 home, -$300,000 equity) $422,372
7 $37,500 $124,346 $262,500 None $474,346
8 $37,500 $186,716 $300,000 None $536,716
9 $37,500 $261,559 $337,500 None $611,559
10 $37,500 $351,371 $375,000 None $701,371
11 $37,500 $459,145 $412,500 None $809,145
12 $37,500 $588,474 $450,000 None $938,474
13 $37,500 $743,668 $487,500 None $1,093,668
Result
It would take 13 years to reach or exceed a $1,000,000 net worth under this co-op model. This is longer than the plain 20% compounding scenario (~10 years) because the home exchange shifts a large portion of assets out of high-growth equity into a static home value. Compared to the median worker's 47 years (at 5% savings and 7% ROI), this setup accelerates wealth building significantly due to the higher savings rate and returns, plus the tiny house bonus.
If your assumptions differ (e.g., homes appreciate at some rate, or the exchange is a net gain if the home is worth more than $300,000), the timeline could shorten. For instance, if the home grows at 5% annually post-exchange, it would reduce the time to ~12 years (re-run simulation with added home growth). Let me know if you'd like adjustments!

getting something started
09/28/2018

getting something started

Help me get the word out! Help me start Scruggs Energy to mitigate Methane Help me start the Responsible Consumers union to enable working-class people make there own peace of a sustainable pie. Your contribution will give me the confidence to throw my entire retirement savings into this project

https://youtu.be/vOoddP2ROTM
03/27/2015

https://youtu.be/vOoddP2ROTM

birds bank stall and even fly upside down for food Shot at Indian rocks beach Florida with my new go pro

02/15/2015

There is another practical solar out there and I fear my $2000 video is bringing him all the attention I was seaking with olny 3 inquries over the past yeay the stock offer is off the table
Sencerly Frank Scruggs.
The best way to make money is to start a business of your own, or help someone else start one. The richest 1% of Americans saved more money doing this than the rest of us did working.
I'm giving you the opportunity to help me start Practical Solar at one dollar per share, if you have $100. I am placing a $2000 cap on investments because I feel there's only a 10% chance of turning your $100 into $1 million over the next 20 years. Practical Solar is in the very early stages of start up. The first hundred thousand is committed to the research and development and in 2015 we plan to complete a 10% scale prototype and begin the first real house installation.
The reason you have never heard of such an offer is that the rich people who influence the Security and Exchange Commission want first crack at all such opportunities. In 1932, a law was passed that no form of stock could be advertised for sale and investors in new startups had to be millionaires already or experts in the field of the start up. That law was changed in the 2012 Jobs Act. At that time the Security and Exchange Commission was given six months to make the new rules match the new law, and they are still dragging their feet.
So I'm committing a civil disobedience as a form of protest by offering you this stock.

Seven sealed pipes stuck 15 feet in the ground should tell us if we can store heat when groundwater is not available
10/28/2014

Seven sealed pipes stuck 15 feet in the ground should tell us if we can store heat when groundwater is not available

Now I have to drill the wells myself. Victor earned 4,000 shares in Practical Solar LLC by purchasing this Deep Rock wel...
10/04/2014

Now I have to drill the wells myself. Victor earned 4,000 shares in Practical Solar LLC by purchasing this Deep Rock well drilling rig for us.

http://youtu.be/2rpJ2tm8x4s Shares in practical solar could earn you $10,000 for every dollar  invested  (over the next ...
09/28/2014

http://youtu.be/2rpJ2tm8x4s
Shares in practical solar could earn you $10,000 for every dollar invested (over the next 20 years) but I don't have the liberty to sell you practical solar shares. It seems the liberty to do this type of free enterprise is limited to the rich, by the 1932 securities exchange act a qualified investor has to be a millionaire already or an expert in the field. I already tried to raise the money from the rich but found they fund so few projects that their money was not available to me. This is why I am offering it to you through a website that is based in the Cayman Islands and the actual transaction would not use US dollars but light coin. The way it would work if you would send me a check or PayPal. My e-mail or purchase stock online in my old website and I would give you two receipts one for the purchase of light coin and the other for the purchase of stock with that light coin .Then you can use the difference in the amount of monies worth of light coin you purchase to buy the stock and what you get back in cash from selling light coin when you sell the stock to do your taxes. Sure there is probably a 90% chance that practical solar would fail before anyone saw such returns but it bothers me that were not allowed to try.

Three thermocouple chips turn 40° DT into electricity and run the 1 1/2 V Motor

04/18/2014

Many have asked for more information so hear is the Narrative of our SBIR grant attempt
The idea is: summer’s heat can be stored in pre-existing subterranean geology for space heat in winter; winter's cold can be stored similarly for air-conditioning in the summer. Electric power can be generated by the difference in temperature between hot and cold storage.

The idea was stumbled upon in another project. We had to air-condition a sealed greenhouse. To do this we pumped 50-degree groundwater from a well through an evaporative water cooling tower inside the greenhouse. This removed 300,000 BTU an hour. The water was returned to the ground through a drain field located over the well. The system worked fine until the well temperature started to increase by 2° a month. We realized that the earth was not dissipating the heat as we had assumed it would, but was allowing it to accumulate.

Later we did computer simulations on three methods of transferring heat into and out of the ground. The first was the “well and drain field” method.


The advantages to this method are: it is nearest to standard well and drain field designs, and permits are easily obtained. The drawback is: hot water applied to the drain field loses heat from the top of the storage area.

The second method we calculated was a “closed loop geothermal transfer system”. This system works by moving water inside the wells but never allows the water to discharge into the groundwater.



The advantages of the system are: permits are the easiest to obtain, and refrigerants such as Freon™, oil, or antifreeze can be used. The disadvantages of the system are: it has the lowest efficiency rate, and costs the most. This system may require 25, 6-inch diameter wells where the open loop groundwater system requires only two 2-inch diameter wells.

The third system we simulated was the “open loop groundwater system.” In this system, solar-heated water is injected into a hot well and an equal amount of cool ground water is withdrawn from a nearby well. The subterranean heat transfer in this model is enormous, and when it is time to use the heat from the system, reversing the flow allows the retrieval of heat at nearly the injection temperature. Call this the “open loop groundwater system.” This system is the most elegant and practical way to transfer heat in and out of pre-existing subterranean geology. The trouble with the open loop groundwater system is political. This system is in common use in Canada in ground water heat pumps, but the Michigan permitting procedure is cumbersome and expensive. The open system can clearly reach our goals of $.06/kilowatt hour for on-demand solar space heat, and $9/million BTU removed in air-conditioning. We must eventually get the state to ease the permitting procedure.

The projected cost of the system ($20,000) is divided by the expected system lifetime (10 yrs) to estimate our cost of energy used





To reach the above stated goals long-term thermal storage must be accompanied by durable cheap flat plate or concentrated solar collectors. This will be phase 2 work. But long-term thermal storage has an intrinsic advantage that is not apparent. The ability to store heat for a long period of time allows us to tap seasonal change. Seasonal change in our area (Michigan) will provide an extra 50° T. This boosts overall system efficiency by 30 to 40%. Considering long-term thermal storage never truly reaches steady state and that it will take two years to reach a level of functional steady state, it is obvious we will not reach the of $.06/kilowatt hour for on-demand solar space heat goals in the phase one program. What we can do in Phase 1 is prove that heat can be stored in the ground for several months, retrieved and used for space heat


Production target cost goals for a 1000 square-foot home:
1000 ft2 of solar collectors $9,000
4 wells at $1000 each: $4,000
large radiator $2,000
installation $5,000
----------------------------------------------------------------------------------------
system cost $20,000

Current service life for this type collector is four years we hope to extend that in the phase one project by never allowing the collector to idle in full sun in summer and by keeping it above 35° in winter by maintaining ground water flow. This water will be stored in a separate well for air conditioning. In phase two we plan to use a proprietary UV block glazing. This solar glazing may be classified as multiple layers of Tedlar bubble packing adhered to the surface.

Much of the cost of photovoltaic systems is this support structure and cell protective glazing. By combining solar thermal and solar photovoltaic we see advantages to both. Capturing the waste heat generated also cools the PV cells. In phase two we plan to test our fixed four to one trough water-cooled PV collector idea. And to compare and contrast water-cooled flat plate and other concentrating collectors designs.

Our first approach will be to use a 1000 square-foot polypropylene flat-plate collector with two layers of polycarbonate glazing to create 130°F water to inject into a 40 ft.-deep hot well. A separate well, 30 ft. from the hot well will supply the collector.

As the hot water migrates it will transfer heat to the surrounding porous media.

The ideal storage reservoir requires permeable material. Experienced drill operators know that when the flushing water level decreases, permeable material has been reached.
A very large radiator measuring approximately 5 x 9 x 7.5, constructed from 90 sheets of Plasticor™ with a supplemental fan will be installed in a home heating system to act as a low-grade heat transfer medium for home heating and cooling. To test electrical generation, we will use 2 100hp tube and shell heat exchangers. These will be charged with R134a refrigerants and used as a boiler and condenser in a Rankine cycle. A five-horse vein motor will be used in place of a turbine. A hydraulic gear pump will be used as a condensate pump, and a small 200 watt motor used as a generator. All 4 wells will be constructed to allow water to be pumped into and out of each well. Throughout the system, flow meters and recording thermometers will monitor each thermodynamic process.

To calculate the thermal storage size required for a project, we use the thumb rule of 72% of annual thermal usage. To get annual thermal usage we look at the gas bill and convert the cu.ft. of gas into BTU by the conversion factor 1 cu.ft. natural gas = 1030 BTUs. Multiplying 153,000 cu.ft. used at our St Clair Shores location by 1030 x .72, we get BTU usage of 113 million BTU per heating season.

Thermal Storage Capacity of Earthen Materials
Substance Specific Heat Capacity
- cp -
(cal/gramoC) (J/kgoC)
Air, dry (sea level) 0.24 1005
Granite 0.19 790
Sandy clay 0.33 1381
Quartz sand 0.19 830
Water, pure 1.00 4186
Wet mud 0.60 2512
• 1 calorie = 4.186 joules = 0.001 Btu/lbmoF
• 1 cal/gramoC = 4186 J/kgoC

We can see from this chart from the Engineering Toolbox that earthen materials have a wide range of specific heat capacities. Taking an average of the sandy clay, quarts sand, and wet mud and converting that number to BTUs per cubic foot degree Fahrenheit we arrived at a specific heat capacity for calculation of 27.4 BTU/ft3 F. Assuming a 30°F T we get a require storage volume of 100,000 ft.³

The heat loss rate from thermal storage depends on the size the storage volume, how many years it has been used at the same location, and the thermal heat capacity of the soil.

“The thermal conductivity of soils is mostly controlled by water content, although, obviously, the type of soil is also important. For an average clay, the thermal conductivity in W/(m K) is 0.25 for no soil moisture, about 1.0 for 10% soil moisture (% by volume), 1.25 at 14% (a bend in the thermal conductivity curve occurs here), 1.67 at 30%, and about 2.0 at 50%. That will give you a rough idea.”
- David R. Cook Atmospheric Section Environmental Research Division Argonne National Laboratory
To simplify; all this thermal conductivity can be thought of as somewhere between R 0.1/inch to R1/inch. In a worst-case scenario, a foot of soil can be considered to have an R-value of 1.2. To retain half the solar energy for heating, the thermal storage area needs to be insulated twice as well as the house, so if the R value of the house is R12 then the thermal storage must have R24. At R.1/inch you would need 20 ft. of soil on all sides. Fortunately pre-existing subterranean geology usually includes more than 20ft of insulation. Under the best circumstances our storage medium would only have to be embedded in a 2 ft. thick layer of insulating soil. You may think this is irrelevant because almost all applications will have a near infinite amount of soil on all sides except the top. The problem is: the insulation layer is not effective until it is charged with a thermal gradient; this is the reason that operating a new heat storage area is so inefficient during the first-year of operation.
Since the insulation layer requirements do not change with the scale of the project, the bigger the project, the more efficient the storage.
U =62 = R70 radiating through 12ft of soil in all directions for 8760 hours/year
A = (31.6ft dimension of the storage + 12ft insolating thickness)² x 6 sides = 11406 ft²
∆t = 80°F (130°F -°50F ambient soil = 80°F)

The vertical axis on this graph shows the distance from a hot well injection on a 50 ft. scale.
The horizontal axis shows 350-day years divided into 50 day increments.
We can clearly see how the light blue insulation layer grows and why the thermal storage return increases over time. The fact that the cold blue reclaims part of the thermal insulation boundary during the time of heat extraction implies some waste heat is being reclaimed.
The following solar radiation maps show three different solar radiation conditions. First is the average annual solar radiation. This type information is viable in sizing solar collectors. The second map shows that most of the annual heat absorbed is during the summer, and gives a rough idea of how fast we have to store heat in the summer. The third map illustrates the difficulty of attempting to gather enough solar energy to heat a building in winter in northern climates.



Research plan
Drill four wells.
Determine the local subsurface water flow rate.
Determine the static water height in each well.
If the static water height is less than 30 ft. from the surface, cross connect the four wells and draw a vacuum on top. Flow meters will show the magnitude of the water migration problem.
If the static water level is greater than 30 ft., this simple procedure will not work and we would be forced to use thermal migration to indicate this problem.
Eight columns of thermal probes placed around the hot well will provide data for water migration and thermal conductive heat migration.
With the water migration rate established we can determine if it will be a problem.
Migration is detected by a difference in temperature in probes 4,5,6,and 7.
If water migration is a problem, we will stagnate this flow by pumping water from the high side around the storage wells to the low side.

Thermal streaming occurs when a narrow channel of water runs directly from a hot well to the warm well. To detect thermal streaming, columns of thermal probes will be strategically placed near the hot well. In the illustration below, probe 5 and probe 4 will be compared. If the temperature of probe 5 is greater than probe 4, thermal streaming is occurring.
Water convection can be an aid to inner storage heat transfer but can be a problem if it occurs in the insulation layers beyond the heat storage area. To detect this, we will use 4 more columns of thermal probes in the heat storage boundary, collinear with the hot well and equidistant from the warm well.

Bacteria growth analysis can be conducted with water samples from the solar panel testing and from the well thermodynamic testing. To record the thermodynamic properties of our wells we will require; a recording flow meter, and a recording thermometer for each well. The wells natural ability to accept injected water will determine the parameters of the heat storage testing. Hot water will be continuously injected (as it is produced by the solar panels) for 100 days. This water will be pumped from the warm well, solar-heated to 130° and injected and into the hot well.
The system will be allowed to stand for 100 days. Water from the hot well is then pumped back into the warm well. The volume and temperature from the hot well will be measured over time.
To see if ambient temperature change over time can be converted into usable electric power we propose the following tests:

Build a thermo-electric generating test rig as follows. Use a tubing shell heat exchanger rated at approximately 100 horsepower of heat transfer as a refrigerant boiler. Use a similar heat exchanger as a condenser. Use a five horsepower vain motor as a turbine and a 200 W DC motor as a generator. Connect these components to form a Rankine cycle. Demonstrate lighting a light bulb with the following heat sources and heat sinks.

1) Use the very "large radiator" as a heat source on a 80°F summer day for the refrigerant boiler. Use groundwater from a natural cold well as a heat sink for the condenser. Take a video of the results.

2) Use the discharge from the hot well storage test as a heat source, and groundwater as a heat sink. Video the results.

3) Use natural groundwater as a heat source and the very large radiator, this time with antifreeze, as the heat sink when the temperature outside is below 10°F.

Hopefully it will not take much imagination to identify a new untapped power source, made possible by long-term thermal storage. We do not expect that this power source will have many stand-alone applications but we do expect it to boost the efficiency of many systems already in place.

Works instrumental in proving the viability of our proposal include:

Meyers, Charles F. and David Todd, Environmental Science and Technology, Volume Seven, New York: 1973, Page 512.

US Patent 3931851, Liquid Aquifer Energy Stora

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