{"id":16587,"date":"2026-09-18T09:26:41","date_gmt":"2026-09-18T07:26:41","guid":{"rendered":"https:\/\/www.bitcoinstuffstore.com\/?post_type=product&#038;p=16587"},"modified":"2026-11-09T22:11:00","modified_gmt":"2026-11-09T21:11:00","slug":"ofen-3-base","status":"publish","type":"product","link":"https:\/\/www.bitcoinstuffstore.com\/en_us\/product\/ofen-3-base\/","title":{"rendered":"21energy Ofen 3 Base"},"content":{"rendered":"<div class=\"bss-product-content\">\n<ul class=\"bss-spec-list\">\n<li><strong>Heat output<\/strong>: 1.0 kW<\/li>\n<li><strong>Suitable for rooms up to<\/strong>: 50 m\u00b2<\/li>\n<li><strong>Hashrate<\/strong>: 40 TH\/s<\/li>\n<li><strong>Efficiency<\/strong>: 20 J\/TH<\/li>\n<li><strong>Noise level<\/strong>: about 35 dB<\/li>\n<li><strong>Dimensions (w \u00d7 h \u00d7 d)<\/strong>: 90 \u00d7 32 \u00d7 14 cm<\/li>\n<li><strong>Weight<\/strong>: about 17 kg<\/li>\n<li><strong>Power connection<\/strong>: regular wall outlet, 230 V<\/li>\n<li><strong>Network<\/strong>: Wi-Fi<\/li>\n<li><strong>Controls<\/strong>: 21energy app (iOS, Android), Home Assistant, open API<\/li>\n<li><strong>Thermostat<\/strong>: yes, via the included RuuviTag<\/li>\n<li><strong>Colors<\/strong>: white, black<\/li>\n<li><strong>Warranty<\/strong>: 12-month manufacturer's warranty plus statutory rights<\/li>\n<li><strong>Delivery time<\/strong>: 3 to 5 business days<\/li>\n<li><strong>Made in<\/strong>: Austria<\/li>\n<\/ul>\n<h2>Buy the 21energy Ofen 3 Base: heat your room and mine bitcoin at the same time<\/h2>\n<p>The 21energy Ofen 3 Base is a 1 kW wall heater with a bitcoin miner inside. The heat is exactly the same as from any other 1 kW electric heater; the difference is that the chips producing the heat work on the Bitcoin network in the meantime, at 40 TH\/s, and you get sats back for it. It's the entry model of the series and, at 14 centimeters deep, the slimmest of the four. At 35 dB it's quieter than a fridge, so it can go in a living room, bedroom or home office. This is the Ofen to start with if you've never had a miner in your home.<\/p>\n<h2>How the Ofen 3 works<\/h2>\n<p>A bitcoin miner turns almost all the electricity it uses into heat; that's physics, not a side effect. 21energy builds a heater around it: chips in a closed housing with a quiet fan, warm air out the top, and in the meantime the miner works on the Bitcoin network. You set it up in three minutes with the 21energy app: connect to Wi-Fi, enter your pool details, done. Schedules, a thermostat via the included RuuviTag, Home Assistant and an open API are all built in. The mined bitcoin arrives in your pool account and you send it on to your own wallet.<\/p>\n<h2>Honest about the costs<\/h2>\n<p>At the average Dutch electricity rate, electric heating costs more than gas or a heat pump, even with a miner inside. The Ofen 3 is, however, the cheapest way to heat electrically, because every other electric heater gives nothing back. It fits three situations: solar panels with a dynamic contract, a room without central heating (garage, workshop, studio, tiny house), or you're a bitcoiner and you simply want one. Heating a regular home with gas and mainly looking to save money? Then this isn't your product, and we'd rather tell you now than after delivery.<\/p>\n<table>\n<thead>\n<tr>\n<th><\/th>\n<th>Per hour at full power<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Electricity (1.0 kW \u00d7 \u20ac0.30)<\/td>\n<td>\u20ac0,30<\/td>\n<\/tr>\n<tr>\n<td>Mined (40 TH\/s)<\/td>\n<td>about \u20ac0.06<\/td>\n<\/tr>\n<tr>\n<td><strong>Net electricity cost<\/strong><\/td>\n<td><strong>about \u20ac0.24<\/strong><\/td>\n<\/tr>\n<tr>\n<td>Regular 1.0 kW electric heater<\/td>\n<td>\u20ac0,30<\/td>\n<\/tr>\n<tr>\n<td>1.0 kW of heat from gas<\/td>\n<td>about \u20ac0.15<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Reference date late August 2026: electricity \u20ac0.30 per kWh, hashprice 38 USD per PH\/s per day, 1 USD = 0.90 EUR, gas \u20ac0.15 per kWh of heat. The hashprice moves daily with the price and the network, so what you mine is never a fixed amount. What is certain: the Ofen uses exactly as much as a regular heater of the same power, and everything the miner earns comes off that. The full calculation is on the category page <a href=\"https:\/\/www.bitcoinstuffstore.com\/en_us\/productcategory\/bitcoin-heating\/\">bitcoin heating<\/a>.<\/p>\n<h2>Base or Pro?<\/h2>\n<p>The Base and the <a href=\"https:\/\/www.bitcoinstuffstore.com\/en_us\/product\/ofen-3-pro\/\">Ofen 3 Pro<\/a> share the same housing, give the same heat and make the same noise. The only difference is the miner inside: 40 TH\/s at 20 J\/TH in the Base, 60 TH\/s at 17.5 J\/TH in the Pro. The Pro gets about a third more hashrate per kilowatt-hour from the same electricity and costs about 800 euros more. If you heat a few hours a day in winter, the Base is the logical choice. If the heater runs for hours every day for half the year, look at the Pro.<\/p>\n<h2>All four models side by side<\/h2>\n<table>\n<thead>\n<tr>\n<th>Model<\/th>\n<th>Heating<\/th>\n<th>Space<\/th>\n<th>Hashrate<\/th>\n<th>Efficiency<\/th>\n<th>Noise<\/th>\n<th>Price<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td><strong>Ofen 3 Base<\/strong><\/td>\n<td>1.0 kW<\/td>\n<td>up to 50 m\u00b2<\/td>\n<td>40 TH\/s<\/td>\n<td>20 J\/TH<\/td>\n<td>35 dB<\/td>\n<td>\u20ac1999,00<\/td>\n<\/tr>\n<tr>\n<td><a href=\"https:\/\/www.bitcoinstuffstore.com\/en_us\/product\/ofen-3-pro\/\">Ofen 3 Pro<\/a><\/td>\n<td>1.1 kW<\/td>\n<td>up to 55 m\u00b2<\/td>\n<td>60 TH\/s<\/td>\n<td>17.5 J\/TH<\/td>\n<td>35 dB<\/td>\n<td>\u20ac2799,00<\/td>\n<\/tr>\n<tr>\n<td><a href=\"https:\/\/www.bitcoinstuffstore.com\/en_us\/product\/ofen-3-base-xl\/\">Ofen 3 Base XL<\/a><\/td>\n<td>2.0 kW<\/td>\n<td>up to 100 m\u00b2<\/td>\n<td>80 TH\/s<\/td>\n<td>20 J\/TH<\/td>\n<td>40 dB<\/td>\n<td>\u20ac2899,00<\/td>\n<\/tr>\n<tr>\n<td><a href=\"https:\/\/www.bitcoinstuffstore.com\/en_us\/product\/ofen-3-pro-xl\/\">Ofen 3 Pro XL<\/a><\/td>\n<td>2.2 kW<\/td>\n<td>up to 110 m\u00b2<\/td>\n<td>120 TH\/s<\/td>\n<td>17.5 J\/TH<\/td>\n<td>40 dB<\/td>\n<td>\u20ac3999,00<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>What's in the box<\/h2>\n<ul>\n<li>The Ofen 3 itself, in white or black<\/li>\n<li>Basic stand to set it up freestanding<\/li>\n<li>RuuviTag temperature sensor for the thermostat function<\/li>\n<li>Power cable for a regular wall outlet<\/li>\n<li>Quick start guide<\/li>\n<\/ul>\n<p>A <a href=\"https:\/\/www.bitcoinstuffstore.com\/en_us\/product\/21energy-wandhouder-ofen-3\/\">wall mount<\/a> or the <a href=\"https:\/\/www.bitcoinstuffstore.com\/en_us\/product\/21energy-premium-voet-ofen-3\/\">premium stand<\/a> is sold separately.<\/p>\n<h2>Frequently asked questions about the Ofen 3 Base<\/h2>\n<div class=\"bss-faq\">\n<div class=\"bss-faq-item is-open\">\n<div class=\"bss-faq-question\">Which Ofen 3 fits my space?<\/div>\n<div class=\"bss-faq-answer\">Base and Pro (about 1 kW, up to 50 to 55 m\u00b2, 35 dB) for a living room, bedroom or office. Base XL and Pro XL (about 2 kW, up to 100 to 110 m\u00b2, 40 dB) for a workshop, garage, studio or large open space. Pro means 50% more hashrate for the same heat.<\/div>\n<\/div>\n<div class=\"bss-faq-item\">\n<div class=\"bss-faq-question\">How much power does the Ofen 3 Base use?<\/div>\n<div class=\"bss-faq-answer\">About 1.0 kW at full power, the same as a regular 1.0 kW electric heater. At \u20ac0.30 per kWh that's \u20ac0.30 per hour. Subtract what the miner earns: about \u20ac0.06 per hour in the example calculation on this page.<\/div>\n<\/div>\n<div class=\"bss-faq-item\">\n<div class=\"bss-faq-question\">How much noise does the Ofen 3 Base make?<\/div>\n<div class=\"bss-faq-answer\">About 35 dB. That's quieter than a fridge, which makes it suitable for a living room or bedroom.<\/div>\n<\/div>\n<div class=\"bss-faq-item\">\n<div class=\"bss-faq-question\">Can I plug the Ofen 3 into a regular wall outlet?<\/div>\n<div class=\"bss-faq-answer\">Yes. The Ofen 3 Base draws 1.0 kW and fits on a standard 16 A circuit. Spread multiple Ofens across different circuits.<\/div>\n<\/div>\n<div class=\"bss-faq-item\">\n<div class=\"bss-faq-question\">Do I need to know about mining?<\/div>\n<div class=\"bss-faq-answer\">No. The 21energy app walks you through the setup in about three minutes. All you need is Wi-Fi and a mining pool account. If you get stuck, we'll help you via WhatsApp.<\/div>\n<\/div>\n<div class=\"bss-faq-item\">\n<div class=\"bss-faq-question\">Can I run the Ofen 3 on a schedule?<\/div>\n<div class=\"bss-faq-answer\">Yes. In the app you set on and off times with a heat level per time slot, and with the included RuuviTag sensor it works as a thermostat on room temperature. Switching it off when you don't need heat is always possible and does the device no harm.<\/div>\n<\/div>\n<div class=\"bss-faq-item\">\n<div class=\"bss-faq-question\">Does the Ofen 3 work with Home Assistant?<\/div>\n<div class=\"bss-faq-answer\">Yes, there's an official Home Assistant integration. You connect other smart home systems through the open API on the device.<\/div>\n<\/div>\n<div class=\"bss-faq-item\">\n<div class=\"bss-faq-question\">Do I need a fast internet connection?<\/div>\n<div class=\"bss-faq-answer\">No, the Ofen 3 uses less than 1 Mbit\/s. What does matter is a stable connection, because the miner stays connected to the pool as long as it's on.<\/div>\n<\/div>\n<div class=\"bss-faq-item\">\n<div class=\"bss-faq-question\">How do I receive the bitcoin the Ofen mines?<\/div>\n<div class=\"bss-faq-answer\">The pool credits your share to your pool account. From there you send it to your own wallet, preferably a <a href=\"https:\/\/www.bitcoinstuffstore.com\/en_us\/productcategory\/hardware-wallets\/\">hardware wallet<\/a> so you hold the keys yourself.<\/div>\n<\/div>\n<div class=\"bss-faq-item\">\n<div class=\"bss-faq-question\">What's the warranty and how long does delivery take?<\/div>\n<div class=\"bss-faq-answer\">12-month manufacturer's warranty from 21energy, on top of your statutory consumer rights with us. Overclocking voids the warranty. The Ofen is shipped by our partner, with a delivery time of 3 to 5 business days.<\/div>\n<\/div>\n<\/div>\n<\/div>","protected":false},"excerpt":{"rendered":"<p><strong>1 kW electric heater that mines bitcoin at 40 TH\/s at the same time.<\/strong><\/p>\n<ul>\n<li><strong>Heats<\/strong>: up to 50 m\u00b2 with 1.0 kW<\/li>\n<li><strong>Mines<\/strong>: 40 TH\/s at 20 J\/TH<\/li>\n<li><strong>Noise<\/strong>: 35 dB, quieter than a fridge<\/li>\n<li><strong>Controls<\/strong>: app, thermostat, Home Assistant<\/li>\n<li><strong>Delivery<\/strong>: 3 to 5 business days, 12-month warranty<\/li>\n<\/ul>","protected":false},"featured_media":16585,"comment_status":"open","ping_status":"closed","template":"","meta":{"rank_math_focus_keyword":"Ofen 3 Base","rank_math_title":"21energy Ofen 3 Base kopen | Stille bitcoin kachel, 40 TH\/s","rank_math_description":"De Ofen 3 Base verwarmt tot 50 m\u00b2 met 1 kW en mined bitcoin met 40 TH\/s. 35 dB, wifi, app, thermostaat. 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