What are the disadvantages to borrowing money for energy conservation measures / solar panels?
"If you sell the property before the ten years are up, the panels might have declined in value more than the amount you owe declined.  In the original post's situation, this is a negligible risk. Suppose (for the sake of argument) that each year's panels are 10% better than the previous year's panels.  Even if the panels lasted forever, and even if the price you could sell the power for stayed the same, then the value of your panels should decline 9% per year.  If the panels are financed at a 4.5% APR for 10 years, your principal should decline by 8.1% in the first year. A second risk is that the solar panels might be ugly, or might go out of fashion.  When selling a home, ""curb appeal"" matters.  If potential buyers do not like how your home looks with the solar panels, you might not be able to get as much money for the house if you have to sell it. A third risk is that the loan might harm your credit rating, or otherwise restrict your ability to borrow.  Even though this deal does not impinge on your disposable income, a bank might think that it raises your debt-service-to-income (DTI) ratio.  This could theoretically prevent you from refinancing your home, or raise the interest rates on potential loans you might want to take out. A fourth risk is that the installation process might damage your home in a way that causes expensive damage.  Water leakage and electrical fires can potentially destroy homes.  You need to have the solar system competently installed. A fifth risk is that the solar power system might make it harder to maintain or replace your roof.  Will your roof need to be replaced during the life of the solar power system?  If so, consider options that do not force you to throw away the solar power system prematurely." "Depending on the details of your solar panel setup, the monthly savings may change depending on changes in the law or utility company policy.  This could change how long it will take for the solar panels to ""pay for themselves"".  So your bullet point about the ""payback period""/""break even point"" is not fixed at the moment you buy the solar panels; it depends on costs you will incur over many years, and those costs could turn out to be different from what you originally thought. At least in the US, home solar installations typically work by selling excess power back to the power company.  The power company can change the amount that it pays you for that power.  There is also typically a minimum charge for being connected to the grid, and the power company can raise that charge.  (This article mentions one such possible change.)  The power companies want to keep making money, and as more people start adding solar panels, the power companies may change their rate structure to make that less financially feasible. You can avoid many of these issues if your solar panels are not connected to the public electricity grid, and you, for instance, store power with your own battery.  However (at least in the US) this is very uncommon because it is more complex and expensive."
When is the right time to buy a new/emerging technology? When it's trading at a discount that allows you to make your money back and then some. The way you presented it, it is of course impossible to say. You have to look at exactly how much cheaper and efficient it will be, and how long that will take. Time too has a cost, and being invested has opportunity cost, so the returns must not only arrive in expected quantity but also arrive on time. Since you tagged this investing, you should look at the financial forecasts of the business, likely future price trajectories, growth opportunity and so on, and buy if you expect a return commensurate with the risk, and if the risk is tolerable to you. If you are new to investment, I would say avoid Musk, there's too much hype and speculation and their valuations are off the charts. You can't make any sensible analysis with so much emotion running wild. Find a more obscure, boring company that has a sound business plan and a good product you think is worth a try. If you read about it on mainstream news every day you can be sure it's sucker bait. Also, my impression that these panels are actually really expensive and have a snowball's chance in Arizona (heh) in a free market. Recently the market has been manipulated through green energy subsidies of a government with a strong environmentalist voter base. This has recently changed, in case you haven't heard. So the future of solar panels is looking a bit uncertain. I am thinking about buying solar panels for my roof. That's not an investment question, it's a shopping question. Do you actually need a new roof? If no, I'd say don't bother. Last I checked the payoff is very small and it takes over a decade to break even, unless you live in a desert next to the Mexican border. Many places never break even. Electricity is cheap in the United States. If you need a new roof anyway, I suppose look at the difference. If it's about the same you might as well, although it's guaranteed to be more hassle for you with the panels. Waiting makes no sense if you need a new roof, because who knows how long that will take and you need a roof now. If a solar roof appeals to you and you would enjoy having one for the price available, go ahead and get one. Don't do it for the money because there's just too much uncertainty there, and it doesn't scale at all. If you do end up making money, good for you, but that's just a small, unexpected bonus on top of the utility of the product itself. "This is the best tl;dr I could make, [original](http://wvtf.org/post/first-time-history-solar-jobs-outnumber-coal-jobs-virginia#stream/0) reduced by 69%. (I'm a bot) ***** &gt; Virginia now has more jobs in the solar industry than the coal industry.  &gt; &amp;quot;Coal will produce more jobs I think in the long term. But we&amp;#039;ve had to cut back because everyone feels like it&amp;#039;s not worth it to use coal anymore. And I feel that there will be a time when we will have to turn back to coal to meet the demand.""  &gt; Alexander Winn at the Solar Foundation says he&amp;#039;s hopeful some of those jobs might move from coal to solar.   ***** [**Extended Summary**](http://np.reddit.com/r/autotldr/comments/6hsj3r/for_first_time_in_history_solar_jobs_outnumber/) | [FAQ](http://np.reddit.com/r/autotldr/comments/31b9fm/faq_autotldr_bot/ ""Version 1.65, ~146519 tl;drs so far."") | [Feedback](http://np.reddit.com/message/compose?to=%23autotldr ""PM's and comments are monitored, constructive feedback is welcome."") | *Top* *keywords*: **coal**^#1 **solar**^#2 **industry**^#3 **Virginia**^#4 **Energy**^#5" Is it possible for Saudi Arabia to create that much renewable energy to replace oil?  Saudi Aramco itself is estimated to be a trillion dollar company. In terms of Solar energy, America just has more land to farm solar.   Where will their edge come from?  Maybe cause political unrest/financial instability of many middle eastern countries? Don't misunderstand man, I'm all about alternative energy.  I bought a Japanese Delica because they have the room I need and they're stupidly good on diesel.  (sadly, I blew the head at Christmas, now I need to get a new one, and until then I'm in an 07 Caravan).  I'd like to add solar panels to the farmhouse once all the other expenses are taken care of, and over the winter we only burn wood for heat in a high-efficiency triple-burn woodstove. Well you would have to take into account 2 things. 1 the taxes and regulations that fossil fuel industries face relative to renewables. 2. subsidies as a percent of fossil fuel industry compared to subsidies as a percent of green energy companies. My hunch is that both of these points show that overall, the fossil fuel industry isn't benefiting from the government and renewable companies are benefiting Disvestment activities tend to be misguided. In doing so, a fund/individual is not really taking money away from the companies in question (assuming they're not doing secondary offerings), and 'disvestment' doesn't imply that you're going to be using their products less (or boycotting them entirely), which would actually impact their financials. And in a convoluted way, disvestment could actually trigger further consolidation among coal companies, since it makes them cheaper and thus easier takeover targets.   Funds that have the ability to do so should make 2nd &amp; 3rd round VC investments in clean energy startups. It's been awfully difficult for clean energy startups to raise money lately, and funding those startups would have a lot more impact. "The other answers are good, I would just like to add certain points, taking this question together with the previous ones you have asked here. How can a person measure how much to spend on food, car, bills or rent   from his salary? Is there a formula to keep in check? Basically, it may well be that your best option would be to move to a smaller apartment or worse location to bring down rent, possibly forget about your own study in the worst case, sell the car and use public transportation, eat as many meals as possible at home, bring boxed lunch from home to work, if this applies, etc -- whatever makes a saving and sense to you. Regarding food, this is the point where it is usually possible to save a very significant amount, if you are prepared to make food at home. Unless you are already doing it, look around for articles such as ""living on 20 pounds a week"" or so, maybe they will give you ideas you can use (eg. How to eat on 10 pounds a week: shopping list and recipes) -- where you are shopping is crucial here as similar items can differ in price significantly between different chains. If the electricity bill is significant and you are at home a lot, you could try to bring it down by changing all bulbs in your home to LED ones, unless it has already been done. Yes, they can cost 2-3 more than eg. halogen ones, but they use 5-10x less electricity. Forget credit cards, if possible. Use debit cards so you know the money you spend does not get you into more debt. One question you asked here was about exchange rates -- if you work with different currencies a lot, there are several companies such as Revolut or N26, which offer accounts with debit cards that use near FX rates --- in my experiencee I could save around 10-15% on currency conversion EUR/GBP, using Revolut, compared to my local bank rate, for example. I find myself looking at my account every single day and get tensed   and sad because almost whenever the money (pay) comes in I freak out   that after everything there is nothing for us to enjoy or save. Well, yes. That is nearly the definition of too much debt. The point about going to the extremes of reducing expenses I outlined above, is that the more you can reduce your expenses while struggling with debt, the faster you'll get out of it. It might be hard to adapt, but it will be better, if you can calculate how long it will take to get you back on feet and know that, eg. ""in 6 months I can start to think of savings and carefully upgrading my lifestyle back"".  In turn, the smaller the reduction of expenses, the more prolonged the process -- you might be looking at 2-3 years of insecure/constantly frustrating/risking more debt lifestyle, instead of 6 months of severely reduced one. Alternatively, if things go too bleak, you might consider declaring bankrupcy -- although I am not sure how feasible it is in the UK." "You want to ""begin building a nice portfolio"" comprised of ""real estate"" and ""solar and wind"".  There are ways to do that without starting your own solar power farm or buying giant wind turbines, or whole apartment complexes. They're called ETFs. They're diversified and it's unlikely that you'll use the entirety of your initial investment."