JP3990527B2

JP3990527B2 - Cogeneration system

Info

Publication number: JP3990527B2
Application number: JP2000063750A
Authority: JP
Inventors: 義孝栢原; 伸岩田; 桂嗣滝本; 豊吉田; 道久末平; 英明藤川
Original assignee: Osaka Gas Co Ltd
Current assignee: Osaka Gas Co Ltd
Priority date: 2000-03-08
Filing date: 2000-03-08
Publication date: 2007-10-17
Anticipated expiration: 2020-03-08
Also published as: JP2001248908A

Description

【０００１】
【発明の属する技術分野】
本発明は、発電機とガスエンジンとを一体化したものとか燃料電池といった熱電併給装置で発生する排熱を利用して、温度成層を形成する状態で貯湯タンク内に湯を貯め、その貯湯タンク内の湯を風呂に供給できるとともに、排熱を利用して風呂の追焚きも行えるように構成したコージェネレーションシステムに関する。
【０００２】
【従来の技術】
従来一般に、風呂の追焚きを行う場合、特開平７−２５３２２８号公報に示されるように、浴槽との間で浴槽内の湯を循環する循環配管を設け、その循環配管にヒータを設け、追焚き時には、ヒータからの熱源によって加熱するように構成されている。
【０００３】
【発明が解決しようとする課題】
しかしながら、熱電併給装置からの排熱を利用して貯湯タンク内に湯を貯め、その湯を風呂に供給できるように構成した場合に、追焚きをヒータなどの専用熱源のみによって行うことは、省エネルギー性や経済性を向上できず、未だ改良の余地があった。
【０００４】
一方、熱電併給装置からの排熱を利用する場合、熱電併給装置の筐体が大きいため、その運転開始時から所定の時間までの立ち上がりにおいて、発生した排熱が筐体や排熱を供給する配管などに吸収され、利用できる排熱量が少ない。
【０００５】
そのような排熱量の少ない状態での加熱を行うと、排熱利用の目的である本来の省エネルギー性や経済性が損なわれる欠点があった。
【０００６】
本発明は、このような事情に鑑みてなされたものであって、請求項１に係る発明は、追焚きを行うときに、熱電併給装置からの排熱を合理的に利用して省エネルギー性および経済性を向上できるようにすることを目的とし、また、請求項２に係る発明は、熱電併給装置の運転状態をも考慮して省エネルギー性および経済性を一層向上できるようにすることを目的とし、また、請求項３に係る発明は、省エネルギー性および経済性の向上を確保しながら、使い勝手に優れたものにできるようにすることを目的とする。
【０００７】
【課題を解決するための手段】
請求項１に係る発明は、上述のような目的を達成するために、
下部から取り出して上部から供給する循環配管を付設して温度成層を形成する状態で貯湯を行う貯湯タンクと、
前記循環配管に設けられて前記貯湯タンクから取り出した水を加熱する加熱手段と、
前記循環配管に設けられて前記貯湯タンクから水を取り出すとともに加熱後の湯を前記貯湯タンクに供給する循環ポンプと、
前記貯湯タンクに連通接続されて前記貯湯タンク内の湯を浴槽内に供給する湯張り手段と、
前記貯湯タンクと並列に前記循環配管に接続されて前記加熱手段を経た湯を取り出す循環用分岐配管と、
前記循環用分岐配管に設けられて追焚き信号に応答して前記浴槽内の湯を循環させて加熱する追焚き用熱交換器とを備えた貯湯式風呂追焚き機能付給湯器において、
前記加熱手段が、熱電併給装置の排熱を熱源とする排熱加熱手段と、加熱能力が高い専用熱源による補助加熱手段とから成り、
前記浴槽内の湯の温度を測定する浴槽温度センサと、
前記浴槽内の湯の沸かし上げ温度を設定する沸かし上げ温度設定手段と、
前記追焚き信号に応答して、前記浴槽温度センサで測定される前記浴槽内の湯の温度と、前記沸かし上げ温度設定手段で設定された沸かし上げ温度とに基づいて前記排熱加熱手段で加熱した場合に沸かし上げ温度に達するのに必要な加熱時間を算出する加熱時間算出手段と、
前記加熱時間算出手段で算出された必要加熱時間と前記熱電併給装置の特性を生かすに足る排熱連続運転時間とを比較して、必要加熱時間が排熱連続運転時間よりも長いときに排熱加熱信号を出力するとともに短いときに補助加熱信号を出力する比較手段と、
前記比較手段からの排熱加熱信号に応答して前記排熱加熱手段を起動する状態に、かつ、補助加熱信号に応答して前記補助加熱手段を起動する状態に自動的に切り換える加熱選択手段とを備えて構成する。
【０００８】
ここで、熱電併給装置の特性を生かすに足る排熱連続運転時間とは、用いる熱電併給装置によって設定されるものである。
すなわち、その筐体の容積に伴う運転開始からの排熱の温度の立ち上がり状況と、立ち上がり後の連続運転時間とから、排熱回収効率と発電効率とを求め、それらから省エネルギー性および経済性の面から有用となる全体としての連続運転時間が排熱連続運転時間として設定される。
【０００９】
また、請求項２に係る発明は、前述のような目的を達成するために、
下部から取り出して上部から供給する循環配管を付設して温度成層を形成する状態で貯湯を行う貯湯タンクと、
前記循環配管に設けられて前記貯湯タンクから取り出した水を加熱する加熱手段と、
前記循環配管に設けられて前記貯湯タンクから水を取り出すとともに加熱後の湯を前記貯湯タンクに供給する循環ポンプと、
前記貯湯タンクに連通接続されて前記貯湯タンク内の湯を浴槽内に供給する湯張り手段と、
前記貯湯タンクと並列に前記循環配管に接続されて前記加熱手段を経た湯を取り出す循環用分岐配管と、
前記循環用分岐配管に設けられて追焚き信号に応答して前記浴槽内の湯を循環させて加熱する追焚き用熱交換器とを備えたコージェネレーションシステムにおいて、
前記加熱手段が、熱電併給装置の排熱を熱源とする排熱加熱手段と、加熱能力が高い専用熱源による補助加熱手段とから成り、
前記浴槽内の湯の温度を測定する浴槽温度センサと、
前記浴槽内の湯の沸かし上げ温度を設定する沸かし上げ温度設定手段と、
前記追焚き信号に応答して、前記浴槽温度センサで測定される前記浴槽内の湯の温度と、前記沸かし上げ温度設定手段で設定された沸かし上げ温度とに基づいて前記排熱加熱手段で加熱した場合に沸かし上げ温度に達するのに必要な加熱時間を算出する加熱時間算出手段と、
前記熱電併給装置の連続運転時間を計測する運転時間計測手段と、
追焚き信号に応答して、前記熱電併給装置が運転状態にあるときに、前記加熱時間算出手段で算出された必要加熱時間と前記運転時間計測手段で計測された連続運転時間とを加算して継続運転時間を算出する継続運転時間算出手段と、
前記継続運転時間算出手段で算出された継続運転時間と排熱連続運転時間とを比較して、継続運転時間が排熱連続運転時間よりも長いときに排熱加熱信号を出力するとともに短いときに補助加熱信号を出力する第２の比較手段と、
前記第２の比較手段からの排熱加熱信号に応答して前記排熱加熱手段を起動する状態に、かつ、補助加熱信号に応答して前記補助加熱手段を起動する状態に自動的に切り換える第２の加熱選択手段とを備えて構成する。
【００１０】
また、請求項３に係る発明は、前述のような目的を達成するために、
下部から取り出して上部から供給する循環配管を付設して温度成層を形成する状態で貯湯を行う貯湯タンクと、
前記循環配管に設けられて前記貯湯タンクから取り出した水を加熱する加熱手段と、
前記循環配管に設けられて前記貯湯タンクから水を取り出すとともに加熱後の湯を前記貯湯タンクに供給する循環ポンプと、
前記貯湯タンクに連通接続されて前記貯湯タンク内の湯を浴槽内に供給する湯張り手段と、
前記貯湯タンクと並列に前記循環配管に接続されて前記加熱手段を経た湯を取り出す循環用分岐配管と、
前記循環用分岐配管に設けられて追焚き信号に応答して前記浴槽内の湯を循環させて加熱する追焚き用熱交換器とを備えたコージェネレーションシステムにおいて、
前記加熱手段が、熱電併給装置の排熱を熱源とする排熱加熱手段と、加熱能力が高い専用熱源による補助加熱手段とから成り、
前記浴槽内の湯の温度を測定する浴槽温度センサと、
前記浴槽内の湯の沸かし上げ温度を設定する沸かし上げ温度設定手段と、
前記追焚き信号に応答して、前記浴槽温度センサで測定される前記浴槽内の湯の温度と、前記沸かし上げ温度設定手段で設定された沸かし上げ温度とに基づいて前記排熱加熱手段で加熱した場合に沸かし上げ温度に達するのに必要な加熱時間を算出する加熱時間算出手段と、
沸かし上がり時間を設定する沸かし上がり時間設定手段と、
追焚き信号に応答して、前記沸かし上がり時間設定手段で設定された沸かし上がり時間と排熱連続運転時間とを比較し、沸かし上がり時間が排熱連続運転時間よりも長いときに沸かし上がり時間を出力する第３の比較手段と、
前記第３の比較手段から出力された沸かし上がり時間と前記加熱時間算出手段で算出された必要加熱時間とを比較して必要加熱時間が沸かし上がり時間よりも長いときにその加熱時間差を算出する加熱時間差算出手段と、
前記加熱時間差算出手段で算出された加熱時間差分の加熱量を前記補助加熱手段で得るに足る補助加熱時間を算出する補助加熱時間算出手段と、
前記補助加熱時間算出手段で算出された補助加熱時間だけ前記排熱加熱手段と併用して補助加熱手段を起動する状態に自動的に切り換える補助加熱併用制御手段とを備えて構成する。
【００１１】
【作用】
請求項１に係る発明のコージェネレーションシステムの構成によれば、追焚きを行う追焚き信号が出力されると、浴槽内に実際に貯められている湯の温度と、設定された沸かし上げ温度とに基づき、排熱加熱手段で沸かし上げた場合の必要加熱時間を算出する。
算出された必要加熱時間と排熱連続運転時間とを比較し、設定された沸かし上げ温度まで追焚きするために排熱加熱手段を運転したときに、省エネルギー性および経済性の面から有用かどうかを判断し、有用であると判断したとき、排熱加熱手段を選択し、省エネルギー性および経済性の面での有用性を確保した状態で排熱により追焚きをすることができる。
【００１２】
また、請求項２に係る発明のコージェネレーションシステムの構成によれば、追焚きを行う追焚き信号が出力された時点において、例えば、貯湯、給湯、暖房であるとか発電のためなどに既に熱電併給装置が運転状態にあるときに、その時点までの熱電併給装置の連続運転時間に、これから追焚きするのに必要な加熱時間を加算し、その加算した継続運転時間と排熱連続運転時間とを比較し、設定された沸かし上げ温度まで追焚きするために排熱加熱手段を運転した場合に、省エネルギー性および経済性の面から有用かどうかを判断し、有用であると判断したとき、排熱加熱手段を選択し、省エネルギー性および経済性の面での有用性を確保した状態で排熱により追焚きをすることができる。
【００１３】
また、請求項３に係る発明のコージェネレーションシステムの構成によれば、排熱連続運転時間を越え、かつ、排熱加熱手段だけによる追焚きでは設定された沸かし上がり時間を越える場合に、その越える時間分を埋めるに必要な加熱量を補助加熱手段で得、排熱加熱手段と補助加熱手段の両方によって追焚きを行い、設定された沸かし上がり時間で追焚きを完了することができる。
【００１４】
【発明の実施の形態】
次に、本発明の実施例を図面に基づいて詳細に説明する。
図１は、本発明に係るコージェネレーションシステムの実施例を示す概略構成図であり、ガスエンジンによって発電機を駆動するように構成した熱電併給装置１と貯湯給湯器２とが、ジャケット冷却水の循環配管３と第１の熱交換器４とを介して接続され、貯湯、給湯および暖房に熱電併給装置１からの排熱を利用できるように構成されている。このジャケット冷却水の循環配管３と第１の熱交換器４とによって排熱加熱手段が構成されている。熱電併給装置１としては、燃料電池を用いるものでも良い。
【００１５】
貯湯給湯器２には、貯湯タンク５と、補助熱源機６と、補給水タンク７とが備えられている。
貯湯タンク５の下部から上部にわたって、循環ポンプ８を介装した循環配管９が設けられ、この循環配管９に第１の熱交換器４と補助熱源機６とが直列に設けられている。
循環配管９には流量センサ１０と流量制御弁１１とが設けられている。
【００１６】
以上の構成により、貯湯タンク５の下部から水を取り出し、熱電併給装置１からの排熱によって加熱し、その加熱後の湯を貯湯タンク５の上部から供給し、温度成層を形成する状態で貯湯を行うようになっている。
【００１７】
補助熱源機６は、加熱能力が高い専用熱源として都市ガスにより燃焼加熱するように構成され、熱電併給装置１からの排熱による加熱を行わないときに、または併用して、補助熱源機６による加熱を行い、貯湯、給湯および暖房用の湯を得るように構成されている。前述排熱加熱手段と補助熱源機６とによって、貯湯タンク５から取り出した水を加熱する加熱手段が構成されている。
【００１８】
循環配管９には、第１の熱交換器４および補助熱源機６と並列に循環用分岐配管１３が接続され、その循環用分岐配管１３に暖房用熱交換器１４と追焚き用熱交換器１５が設けられている。
【００１９】
暖房用熱交換器１４には、補給水タンク７に接続される状態で第１のポンプ付き配管１６が接続され、第１のポンプ付き配管１６に取り出しヘッダー１７および戻りヘッダー１８を介して図示していない床暖房機、室内暖房機、浴室乾燥機などが接続されている。
【００２０】
追焚き用熱交換器１５には、第２のポンプ付き配管１９を介して浴槽２０が接続され、追焚きを行うように構成されている。
第２のポンプ付き配管１９には、浴槽２０内に貯められている実際の湯量を測定する圧力センサ２１が設けられている。
【００２１】
循環配管９および出力用循環配管１３と並列に、貯湯タンク５に給湯管２２が接続され、給湯管２２に分配弁２２ａ、流量制御弁２２ｂ、流量センサ２２ｃおよび開閉弁２２ｄが設けられるとともに、その給湯管２２が第２のポンプ付き配管１９に接続されている。これにより、貯湯タンク５から給湯管２２および第２のポンプ付き配管１９を介して浴槽２０内に所望温度の湯を供給できるように湯張り手段が構成されている。
【００２２】
給湯管２２の途中箇所には、シャワーに接続されるシャワー配管２２ｅが接続されている。分配弁２２ａには、給水管２３が接続され、湯量と給水量との分配比を調節することにより湯張り時の湯の温度を調節できるようになっている。
【００２３】
第２のポンプ付き配管１９には、浴槽５内の湯の温度を測定する浴槽温度センサ２４が設けられている。また、浴室（図示せず）の側壁に取り付けられたタッチパネルに、追焚き時に沸かし上げ温度を設定する沸かし上げ温度設定手段２５（図２参照）と、沸かし上がり時間を設定する沸かし上がり時間設定手段２６（図３参照）が設けられている。
【００２４】
熱電併給装置１に、その発電出力を感知するなどにより運転状態を検出するとともに、その連続運転時間を計測する運転時間計測手段２７（図２参照）が設けられている。
【００２５】
図２の（ａ）の第１実施例のブロック図に示すように、浴槽温度センサ２４と沸かし上げ温度設定手段２５がマイクロコンピュータ２８に接続され、そのマイクロコンピュータ２８に排熱加熱手段としての熱電併給装置１と補助加熱手段としての補助熱源機６とが接続されている。
【００２６】
マイクロコンピュータ２８には、加熱時間算出手段２９と比較手段３０と加熱選択手段３１とが備えられている。
加熱時間算出手段２９は、追焚き信号に応答して、浴槽温度センサ２４で測定される浴槽２０内の湯の温度と、沸かし上げ温度設定手段２５で設定された沸かし上げ温度とに基づいて熱電併給装置１からの排熱を利用する排熱加熱手段で加熱した場合に沸かし上げ温度に達するのに必要な加熱時間を算出するようになっている。
【００２７】
比較手段３０は、加熱時間算出手段２９で算出された必要加熱時間と熱電併給装置１の特性を生かすに足る排熱連続運転時間とを比較して、必要加熱時間が排熱連続運転時間よりも長いときに排熱加熱信号を出力するとともに短いときに補助加熱信号を出力するようになっている。
【００２８】
上記排熱連続運転時間は、用いる熱電併給装置１に応じてその熱電併給装置１の特性を生かすに足るように設定されるものである。
すなわち、熱電併給装置１を構成する筐体の容積に伴う運転開始からの排熱の温度の立ち上がり状況と、立ち上がり後の連続運転時間とから、排熱回収効率と発電効率とを求め、それらから省エネルギー性および経済性の面から有用となる全体としての連続運転時間が排熱連続運転時間として設定される。
【００２９】
加熱選択手段３１は、比較手段３０からの排熱加熱信号に応答して排熱加熱手段（熱電併給装置１）を起動する状態に、かつ、補助加熱信号に応答して補助加熱手段（補助熱源機６）を起動する状態に自動的に切り換えるようになっている。
【００３０】
以上の構成により、追焚きを行うときに、省エネルギー性および経済性の面から有用となるときにのみ熱電併給装置１からの排熱を利用し、省エネルギー性および経済性を向上できる。
【００３１】
図２の（ｂ）は第２実施例のブロック図であり、マイクロコンピュータ２８に、継続運転時間算出手段３２と第２の比較手段３３と第２の加熱選択手段３４とが備えられている。
【００３２】
継続運転時間算出手段３２は、追焚き信号に応答して、熱電併給装置１が運転状態にあるときに、加熱時間算出手段２９で算出された必要加熱時間と運転時間計測手段２７で計測された連続運転時間とを加算して継続運転時間を算出するようになっている。
【００３３】
第２の比較手段３３は、継続運転時間算出手段３２で算出された継続運転時間と排熱連続運転時間とを比較して、継続運転時間が排熱連続運転時間よりも長いときに排熱加熱信号を出力するとともに短いときに補助加熱信号を出力するようになっている。
【００３４】
第２の加熱選択手段３４は、第２の比較手段３３からの排熱加熱信号に応答して排熱加熱手段（熱電併給装置１）を起動する状態に、かつ、補助加熱信号に応答して補助加熱手段（補助熱源機６）を起動する状態に自動的に切り換えるようになっている。
【００３５】
この第２実施例の構成によれば、追焚きの分だけでは熱電併給装置１を運転して排熱で加熱しても省エネルギー性および経済性を向上できない場合でも、貯湯、給湯、暖房であるとか発電のためなどに既に熱電併給装置１を運転している場合に、継続して熱電併給装置１を運転させることで排熱連続運転時間を越え、省エネルギー性および経済性を向上できる。
【００３６】
図３は第３実施例のブロック図であり、マイクロコンピュータ２８に、第３の比較手段３５と加熱時間差算出手段３６と補助加熱時間算出手段３７と補助加熱併用制御手段３８とが備えられている。
【００３７】
第３の比較手段３５は、追焚き信号に応答して、沸かし上がり時間設定手段２６で設定された沸かし上がり時間と排熱連続運転時間とを比較し、沸かし上がり時間が排熱連続運転時間よりも長いときに沸かし上がり時間を出力するようになっている。
【００３８】
加熱時間差算出手段３６は、第３の比較手段３５から出力された沸かし上がり時間と加熱時間算出手段２９で算出された必要加熱時間とを比較して必要加熱時間が沸かし上がり時間よりも長いときにその加熱時間差を算出するようになっている。
【００３９】
補助加熱時間算出手段３７は、加熱時間差算出手段３６で算出された加熱時間差分の加熱量を補助加熱手段（補助熱源機６）で得るに足る補助加熱時間を算出するようになっている。
【００４０】
補助加熱併用制御手段３８は、補助加熱時間算出手段３７で算出された補助加熱時間だけ排熱加熱手段（熱電併給装置１）と併用して補助加熱手段（補助熱源機６）を起動する状態に自動的に切り換えるようになっている。
【００４１】
この第３実施例の構成によれば、熱電併給装置１を省エネルギー性および経済性の面で有用な状態で極力長い時間運転して省エネルギー性および経済性を向上できながら、補助熱源機６による加熱により、設定された沸かし上がり時間に確実に沸かし上げ、使い勝手にも優れたものにできる。
【００４２】
本発明としては、前述第１実施例、第２実施例および第３実施例のすべてを備えて貯湯式風呂追焚き機能付給湯器を構成するものでも良い。
【００４３】
【発明の効果】
以上の説明から明らかなように、請求項１に係る発明のコージェネレーションシステムによれば、追焚きを行うために排熱加熱手段を運転した場合に、省エネルギー性および経済性の面から有用であると判断したときに、排熱加熱手段で排熱により追焚きを行うから、熱電併給装置からの排熱を合理的に利用して省エネルギー性および経済性を向上できる。
【００４４】
また、請求項２に係る発明のコージェネレーションシステムによれば、追焚きを行う追焚き信号が出力された時点において、例えば、給湯であるとか発電のためなどに既に熱電併給装置が運転状態にあるときに、その時点までの熱電併給装置の連続運転時間を、これから追焚きを行うのに必要な加熱時間に加算した継続運転時間を基に、追焚きを行うために排熱加熱手段を運転した場合に、省エネルギー性および経済性の面から有用であると判断したときに、排熱加熱手段で排熱により追焚きを行うから、追焚きだけであれば、省エネルギー性および経済性の面から有用である排熱連続運転時間とはならない場合でも、熱電併給装置の運転状態を考慮して排熱により追焚きを行うことができ、省エネルギー性および経済性を一層向上できる。
【００４５】
また、請求項３に係る発明のコージェネレーションシステムによれば、浴槽内の湯が低温で沸かし上げに時間がかかり過ぎるといったように、排熱加熱手段だけによる追焚きでは設定された沸かし上がり時間を越える場合に、排熱加熱手段と補助加熱手段の両方によって追焚きを行うことにより、設定時間で追焚きを完了するから、可能な限り排熱加熱手段による追焚きを行うことができ、省エネルギー性および経済性の向上を確保しながら、設定時間で風呂を沸かし上げることができて使い勝手に優れる。
【図面の簡単な説明】
【図１】本発明に係るコージェネレーションシステムの概略構成図である。
【図２】（ａ）は第１実施例を示すブロック図、（ｂ）は第２実施例を示すブロック図である。
【図３】第３実施例を示すブロック図である。
【符号の説明】
１…熱電併給装置
４…第１の熱交換器
６…補助熱源機
８…循環ポンプ
９…循環配管
１３…循環用分岐配管
１５…追焚き用熱交換器
２０…浴槽
２４…浴槽温度センサ
２５…沸かし上げ温度設定手段
２６…沸かし上がり時間設定手段
２７…運転時間計測手段
２９…加熱時間算出手段
３０…比較手段
３１…加熱選択手段
３２…継続運転時間算出手段
３３…第２の比較手段
３４…第２の加熱選択手段
３５…第３の比較手段
３６…加熱時間差算出手段
３７…補助加熱時間算出手段
３８…補助加熱併用制御手段[0001]
BACKGROUND OF THE INVENTION
The present invention stores hot water in a hot water storage tank in a state in which temperature stratification is formed by utilizing exhaust heat generated by a combined heat and power device such as a generator and a gas engine or a fuel cell, and the hot water storage tank The present invention relates to a cogeneration system configured to supply hot water inside the bath and to replenish the bath using exhaust heat.
[0002]
[Prior art]
Conventionally, when performing bath replenishment, as disclosed in Japanese Patent Laid-Open No. 7-253228, a circulation pipe for circulating hot water in the bathtub is provided between the bathtub and a heater is provided in the circulation pipe. At the time of burning, it is configured to be heated by a heat source from a heater.
[0003]
[Problems to be solved by the invention]
However, if the waste heat from the combined heat and power supply device is used to store hot water in the hot water storage tank and the hot water can be supplied to the bath, it is possible to save energy by using only a dedicated heat source such as a heater. However, there was still room for improvement.
[0004]
On the other hand, when using the exhaust heat from the combined heat and power supply device, since the casing of the combined heat and power supply device is large, the generated exhaust heat supplies the housing and the exhaust heat from the start of operation until a predetermined time. The amount of waste heat that can be absorbed and used by piping is low.
[0005]
When heating is performed in such a state where the amount of exhaust heat is small, there is a drawback that the original energy saving and economical efficiency, which are the purpose of exhaust heat utilization, are impaired.
[0006]
The present invention has been made in view of such circumstances, and the invention according to claim 1 is characterized in that, when performing reheating, the exhaust heat from the combined heat and power supply apparatus is rationally used to save energy and The purpose of the invention is to improve the economic efficiency, and the invention according to claim 2 aims to further improve the energy saving and economic efficiency in consideration of the operating state of the combined heat and power supply apparatus. In addition, an object of the invention according to claim 3 is to enable improvement in usability while ensuring improvement in energy saving and economy.
[0007]
[Means for Solving the Problems]
In order to achieve the above-described object, the invention according to claim 1
A hot water storage tank that stores hot water in a state where a temperature stratification is formed by attaching a circulation pipe that is taken out from the lower part and supplied from the upper part,
Heating means provided in the circulation pipe for heating water taken out from the hot water storage tank;
A circulation pump which is provided in the circulation pipe and takes out water from the hot water storage tank and supplies hot water after heating to the hot water storage tank;
Hot water filling means connected to the hot water storage tank and supplying hot water in the hot water storage tank into the bathtub;
A branch pipe for circulation that is connected to the circulation pipe in parallel with the hot water storage tank and takes out the hot water that has passed through the heating means;
In the hot water storage type hot water supply bath with a hot water storage type bath replenishment function provided with a heat exchanger for reheating that is provided in the branch piping for circulation and circulates and heats the hot water in the bathtub in response to a reheating signal,
The heating means comprises exhaust heat heating means using the exhaust heat of the combined heat and power supply device as a heat source, and auxiliary heating means using a dedicated heat source having a high heating capacity,
A bathtub temperature sensor for measuring the temperature of hot water in the bathtub;
Boiling temperature setting means for setting the boiling temperature of hot water in the bathtub;
Responding to the reheating signal, heating by the exhaust heat heating means based on the temperature of the hot water in the bathtub measured by the bathtub temperature sensor and the boiling temperature set by the boiling temperature setting means Heating time calculating means for calculating the heating time required to reach the boiling temperature when
Comparing the required heating time calculated by the heating time calculating means with the exhaust heat continuous operation time sufficient to make use of the characteristics of the combined heat and power supply device, the exhaust heat is exhausted when the required heating time is longer than the exhaust heat continuous operation time. Comparison means for outputting a heating signal and outputting an auxiliary heating signal when it is short,
A heating selection means for automatically switching to a state in which the exhaust heat heating means is activated in response to the exhaust heat heating signal from the comparison means and to a state in which the auxiliary heating means is activated in response to the auxiliary heating signal; It comprises and comprises.
[0008]
Here, the exhaust heat continuous operation time sufficient to make use of the characteristics of the combined heat and power supply apparatus is set by the combined heat and power supply apparatus used.
In other words, exhaust heat recovery efficiency and power generation efficiency are obtained from the rising state of exhaust heat temperature from the start of operation according to the volume of the casing and the continuous operation time after the start, and energy saving and economic efficiency are obtained from them. The continuous operation time as a whole which is useful from the aspect is set as the exhaust heat continuous operation time.
[0009]
In order to achieve the above-described object, the invention according to claim 2
A hot water storage tank that stores hot water in a state where a temperature stratification is formed by attaching a circulation pipe that is taken out from the lower part and supplied from the upper part,
Heating means provided in the circulation pipe for heating water taken out from the hot water storage tank;
A circulation pump which is provided in the circulation pipe and takes out water from the hot water storage tank and supplies hot water after heating to the hot water storage tank;
Hot water filling means connected to the hot water storage tank and supplying hot water in the hot water storage tank into the bathtub;
A branch pipe for circulation that is connected to the circulation pipe in parallel with the hot water storage tank and takes out the hot water that has passed through the heating means;
In the cogeneration system provided with the heat exchanger for reheating which is provided in the branch piping for circulation and circulates and heats the hot water in the bathtub in response to the reheating signal,
The heating means comprises exhaust heat heating means using the exhaust heat of the combined heat and power supply device as a heat source, and auxiliary heating means using a dedicated heat source having a high heating capacity,
A bathtub temperature sensor for measuring the temperature of hot water in the bathtub;
Boiling temperature setting means for setting the boiling temperature of hot water in the bathtub;
Responding to the reheating signal, heating by the exhaust heat heating means based on the temperature of the hot water in the bathtub measured by the bathtub temperature sensor and the boiling temperature set by the boiling temperature setting means Heating time calculating means for calculating the heating time required to reach the boiling temperature when
An operation time measuring means for measuring a continuous operation time of the cogeneration apparatus;
In response to the follow-up signal, when the combined heat and power device is in an operating state, the required heating time calculated by the heating time calculating means and the continuous operation time measured by the operating time measuring means are added. Continuous operation time calculating means for calculating continuous operation time;
When the continuous operation time calculated by the continuous operation time calculation means is compared with the exhaust heat continuous operation time, and when the continuous operation time is longer than the exhaust heat continuous operation time, the exhaust heat heating signal is output and short Second comparison means for outputting an auxiliary heating signal;
A first switch that automatically activates the exhaust heat heating means in response to the exhaust heat heating signal from the second comparison means and activates the auxiliary heating means in response to the auxiliary heating signal; 2 heating selection means.
[0010]
In order to achieve the above-described object, the invention according to claim 3
A hot water storage tank that stores hot water in a state where a temperature stratification is formed by attaching a circulation pipe that is taken out from the lower part and supplied from the upper part,
Heating means provided in the circulation pipe for heating water taken out from the hot water storage tank;
A circulation pump which is provided in the circulation pipe and takes out water from the hot water storage tank and supplies hot water after heating to the hot water storage tank;
Hot water filling means connected to the hot water storage tank and supplying hot water in the hot water storage tank into the bathtub;
A branch pipe for circulation that is connected to the circulation pipe in parallel with the hot water storage tank and takes out the hot water that has passed through the heating means;
In the cogeneration system provided with the heat exchanger for reheating which is provided in the branch piping for circulation and circulates and heats the hot water in the bathtub in response to the reheating signal,
The heating means comprises exhaust heat heating means using the exhaust heat of the combined heat and power supply device as a heat source, and auxiliary heating means using a dedicated heat source having a high heating capacity,
A bathtub temperature sensor for measuring the temperature of hot water in the bathtub;
Boiling temperature setting means for setting the boiling temperature of hot water in the bathtub;
Responding to the reheating signal, heating by the exhaust heat heating means based on the temperature of the hot water in the bathtub measured by the bathtub temperature sensor and the boiling temperature set by the boiling temperature setting means Heating time calculating means for calculating the heating time required to reach the boiling temperature when
Boil-up time setting means for setting the boil-up time;
In response to the reheating signal, the boiling time set by the boiling time setting means is compared with the exhaust heat continuous operation time, and when the boiling time is longer than the exhaust heat continuous operation time, the boiling time is set. Third comparing means for outputting;
The heating for calculating the difference in heating time when the required heating time is longer than the boiling time by comparing the boiling time output from the third comparing means with the required heating time calculated by the heating time calculating means. A time difference calculating means;
Auxiliary heating time calculating means for calculating an auxiliary heating time sufficient to obtain the heating amount of the heating time difference calculated by the heating time difference calculating means by the auxiliary heating means;
Auxiliary heating combined control means for automatically switching to a state in which the auxiliary heating means is activated in combination with the exhaust heat heating means for the auxiliary heating time calculated by the auxiliary heating time calculating means.
[0011]
[Action]
According to the configuration of the cogeneration system of the invention according to claim 1, when a reheating signal for reheating is output, the temperature of hot water actually stored in the bathtub, the set boiling temperature, Based on the above, the required heating time in the case of boiling by the exhaust heat heating means is calculated.
Whether it is useful from the aspect of energy saving and economy when the exhaust heat heating means is operated to compare the calculated required heating time with the exhaust heat continuous operation time and track it to the set boiling-up temperature When it is determined that it is useful, the exhaust heat heating means is selected, and the exhaust heat can be used for the pursuit of energy saving and economical efficiency.
[0012]
Further, according to the configuration of the cogeneration system of the invention according to claim 2, at the time when a reheating signal for performing reheating is output, for example, for hot water storage, hot water supply, heating, or for power generation, etc. When the device is in operation, add the heating time necessary to follow up to the continuous operation time of the combined heat and power unit up to that point, and add the added continuous operation time and exhaust heat continuous operation time. In comparison, when exhaust heat heating means is operated to track up to the set boiling-up temperature, it is judged whether it is useful from the aspect of energy saving and economical efficiency. A heating means can be selected, and reheating can be performed by exhaust heat in a state where utility in terms of energy saving and economy is ensured.
[0013]
Further, according to the configuration of the cogeneration system of the invention according to claim 3, when the exhaust heat continuous operation time is exceeded and the set-up time is exceeded in the reheating with only the exhaust heat heating means, the excess is exceeded. The heating amount necessary to fill the time is obtained by the auxiliary heating means, and the heating is completed by both the exhaust heat heating means and the auxiliary heating means, and the heating can be completed in the set boiling time.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic configuration diagram showing an embodiment of a cogeneration system according to the present invention, in which a combined heat and power supply device 1 and a hot water storage hot water supply device 2 configured to drive a generator by a gas engine include jacket cooling water. It connects via the circulation piping 3 and the 1st heat exchanger 4, and is comprised so that the waste heat from the cogeneration apparatus 1 can be utilized for hot water storage, hot water supply, and heating. The jacket cooling water circulation pipe 3 and the first heat exchanger 4 constitute exhaust heat heating means. As the cogeneration apparatus 1, a fuel cell may be used.
[0015]
The hot water storage water heater 2 includes a hot water storage tank 5, an auxiliary heat source unit 6, and a makeup water tank 7.
A circulation pipe 9 including a circulation pump 8 is provided from the lower part to the upper part of the hot water storage tank 5, and the first heat exchanger 4 and the auxiliary heat source unit 6 are provided in series in the circulation pipe 9.
The circulation pipe 9 is provided with a flow sensor 10 and a flow control valve 11.
[0016]
With the above configuration, water is taken out from the lower part of the hot water storage tank 5 and heated by exhaust heat from the combined heat and power supply device 1, and hot water after the heating is supplied from the upper part of the hot water storage tank 5 to form a temperature stratification. Is supposed to do.
[0017]
The auxiliary heat source unit 6 is configured to burn and heat with city gas as a dedicated heat source having a high heating capacity, and when the heating by the exhaust heat from the combined heat and power supply apparatus 1 is not performed or in combination, the auxiliary heat source unit 6 It is configured to perform heating and obtain hot water for hot water storage, hot water supply and heating. The exhaust heat heating means and the auxiliary heat source unit 6 constitute a heating means for heating the water taken out from the hot water storage tank 5.
[0018]
A circulation branch pipe 13 is connected to the circulation pipe 9 in parallel with the first heat exchanger 4 and the auxiliary heat source unit 6, and a heating heat exchanger 14 and a reheating heat exchanger are connected to the circulation branch pipe 13. 15 is provided.
[0019]
The heating heat exchanger 14 is connected to a first pump-equipped pipe 16 in a state of being connected to the makeup water tank 7, and the first pump-equipped pipe 16 is illustrated via a take-out header 17 and a return header 18. Not floor heaters, indoor heaters, bathroom dryers, etc. are connected.
[0020]
The chasing heat exchanger 15 is connected to a bathtub 20 via a second pipe 19 with a pump, and is configured to perform chasing.
The second pump-equipped pipe 19 is provided with a pressure sensor 21 that measures the actual amount of hot water stored in the bathtub 20.
[0021]
In parallel with the circulation pipe 9 and the output circulation pipe 13, a hot water supply pipe 22 is connected to the hot water storage tank 5, and a distribution valve 22a, a flow rate control valve 22b, a flow rate sensor 22c, and an on-off valve 22d are provided in the hot water supply pipe 22. A hot water supply pipe 22 is connected to the second pumped pipe 19. Thus, hot water filling means is configured so that hot water of a desired temperature can be supplied from the hot water storage tank 5 into the bathtub 20 through the hot water supply pipe 22 and the second pipe 19 with pump.
[0022]
A shower pipe 22 e connected to the shower is connected to a midpoint of the hot water supply pipe 22. A water supply pipe 23 is connected to the distribution valve 22a, and the temperature of hot water during hot water filling can be adjusted by adjusting the distribution ratio between the amount of hot water and the amount of water supplied.
[0023]
The second pump-equipped pipe 19 is provided with a bathtub temperature sensor 24 that measures the temperature of hot water in the bathtub 5. In addition, on the touch panel attached to the side wall of the bathroom (not shown), a boiling temperature setting means 25 (see FIG. 2) for setting the boiling temperature when reheating, and a boiling time setting means for setting the boiling time 26 (see FIG. 3) is provided.
[0024]
The combined heat and power supply apparatus 1 is provided with an operation time measuring means 27 (see FIG. 2) for detecting the operation state by sensing the generated power output and measuring the continuous operation time.
[0025]
As shown in the block diagram of the first embodiment of FIG. 2A, a bathtub temperature sensor 24 and a boiling temperature setting means 25 are connected to a microcomputer 28, and a thermoelectric as exhaust heat heating means is connected to the microcomputer 28. The co-feeder 1 and an auxiliary heat source machine 6 as auxiliary heating means are connected.
[0026]
The microcomputer 28 includes a heating time calculation unit 29, a comparison unit 30, and a heating selection unit 31.
The heating time calculation means 29 responds to the reheating signal based on the temperature of the hot water in the bathtub 20 measured by the bathtub temperature sensor 24 and the boiling temperature set by the boiling temperature setting means 25. The heating time required to reach the boiling temperature is calculated when heated by the exhaust heat heating means using the exhaust heat from the co-feeder 1.
[0027]
The comparison means 30 compares the required heating time calculated by the heating time calculation means 29 with the exhaust heat continuous operation time sufficient to make use of the characteristics of the combined heat and power supply device 1, and the required heating time is more than the exhaust heat continuous operation time. When it is long, an exhaust heat heating signal is output, and when it is short, an auxiliary heating signal is output.
[0028]
The exhaust heat continuous operation time is set so as to take advantage of the characteristics of the combined heat and power supply device 1 according to the combined heat and power supply device 1 used.
That is, the exhaust heat recovery efficiency and the power generation efficiency are obtained from the rising state of the exhaust heat temperature from the start of operation according to the volume of the casing constituting the combined heat and power supply apparatus 1 and the continuous operation time after the start, The overall continuous operation time that is useful in terms of energy saving and economy is set as the exhaust heat continuous operation time.
[0029]
The heating selection means 31 is in a state in which the exhaust heat heating means (heat cogeneration apparatus 1) is activated in response to the exhaust heat heating signal from the comparison means 30, and in response to the auxiliary heating signal, the auxiliary heating means (auxiliary heat source). The machine 6) is automatically switched to the starting state.
[0030]
With the above-described configuration, the exhaust heat from the combined heat and power supply apparatus 1 can be used only when it is useful from the aspect of energy saving and economical efficiency, and the energy saving and economical efficiency can be improved.
[0031]
FIG. 2B is a block diagram of the second embodiment, and the microcomputer 28 is provided with a continuous operation time calculation means 32, a second comparison means 33, and a second heating selection means 34.
[0032]
The continuous operation time calculation means 32 is measured by the required heating time calculated by the heating time calculation means 29 and the operation time measurement means 27 when the cogeneration apparatus 1 is in an operating state in response to the tracking signal. The continuous operation time is calculated by adding the continuous operation time.
[0033]
The second comparison means 33 compares the continuous operation time calculated by the continuous operation time calculation means 32 with the exhaust heat continuous operation time, and when the continuous operation time is longer than the exhaust heat continuous operation time, the exhaust heat heating is performed. A signal is output and an auxiliary heating signal is output when the signal is short.
[0034]
The second heating selection means 34 is activated in response to the exhaust heat heating signal from the second comparison means 33 and activates the exhaust heat heating means (the combined heat and power supply device 1), and in response to the auxiliary heating signal. The auxiliary heating means (auxiliary heat source unit 6) is automatically switched to a starting state.
[0035]
According to the configuration of the second embodiment, hot water storage, hot water supply, and heating can be achieved even when the combined heat and power supply device 1 is operated and heated with exhaust heat and the energy saving and economic efficiency cannot be improved by the additional heating. When the cogeneration apparatus 1 is already operated for power generation or the like, the continuous operation time of the exhaust heat can be exceeded by continuously operating the cogeneration apparatus 1, thereby improving energy saving and economy.
[0036]
FIG. 3 is a block diagram of the third embodiment. The microcomputer 28 is provided with a third comparison means 35, a heating time difference calculating means 36, an auxiliary heating time calculating means 37, and an auxiliary heating combined control means 38. .
[0037]
In response to the reheating signal, the third comparing means 35 compares the boiling time set by the boiling time setting means 26 with the exhaust heat continuous operation time, and the boiling time is greater than the exhaust heat continuous operation time. Even when it is long, it is designed to output the boiling time.
[0038]
The heating time difference calculating means 36 compares the boiling time output from the third comparing means 35 with the required heating time calculated by the heating time calculating means 29, and when the required heating time is longer than the boiling time. The heating time difference is calculated.
[0039]
The auxiliary heating time calculating means 37 calculates the auxiliary heating time sufficient to obtain the heating amount of the heating time difference calculated by the heating time difference calculating means 36 by the auxiliary heating means (auxiliary heat source unit 6).
[0040]
The auxiliary heating combined use control means 38 is in a state where the auxiliary heating means (auxiliary heat source machine 6) is activated in combination with the exhaust heat heating means (heat-electric co-supplying device 1) for the auxiliary heating time calculated by the auxiliary heating time calculating means 37. It is designed to switch automatically.
[0041]
According to the configuration of the third embodiment, the combined heat and power supply apparatus 1 can be operated for a long time as much as possible in a state that is useful in terms of energy saving and economy, and the energy saving and economy can be improved while heating by the auxiliary heat source unit 6 is performed. Thus, it can be surely boiled at the set boil-up time, and can be made easy to use.
[0042]
As the present invention, the hot water heater with a hot water storage type bath replenishing function may be configured by including all of the first embodiment, the second embodiment, and the third embodiment.
[0043]
【The invention's effect】
As is clear from the above description, the cogeneration system according to the first aspect of the invention is useful in terms of energy saving and economical efficiency when the exhaust heat heating means is operated in order to carry out reheating. When it is determined that the exhaust heat is replenished by the exhaust heat heating means, the exhaust heat from the combined heat and power supply device can be rationally used to improve energy saving and economy.
[0044]
According to the cogeneration system of the invention according to claim 2, at the time when the reheating signal for reheating is output, the combined heat and power supply device is already in operation, for example, for hot water supply or for power generation. Sometimes, the exhaust heat heating means was operated to perform the reheating based on the continuous operation time obtained by adding the continuous operation time of the combined heat and power system up to that time to the heating time necessary for the renewal. In this case, when it is judged that it is useful from the aspect of energy saving and economic efficiency, it is replenished by exhaust heat with the exhaust heat heating means. Even when the exhaust heat continuous operation time is not reached, it is possible to replenish by exhaust heat in consideration of the operation state of the combined heat and power supply device, and energy saving and economic efficiency can be further improved.
[0045]
Further, according to the cogeneration system of the invention according to claim 3, the set boiling time is set by the reheating only by the exhaust heat heating means such that the hot water in the bathtub takes too long to boil at a low temperature. If the temperature exceeds the limit value, both the exhaust heat heating means and the auxiliary heating means perform the tracking, and the tracking is completed in the set time. Therefore, the exhaust heat heating means can be used as much as possible to save energy. In addition, while ensuring improved economic efficiency, the bath can be boiled in a set time, making it easy to use.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a cogeneration system according to the present invention.
2A is a block diagram showing a first embodiment, and FIG. 2B is a block diagram showing a second embodiment.
FIG. 3 is a block diagram showing a third embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Combined heat and power supply apparatus 4 ... 1st heat exchanger 6 ... Auxiliary heat source machine 8 ... Circulation pump 9 ... Circulation piping 13 ... Circulation branch piping 15 ... Reheating heat exchanger 20 ... Bathtub 24 ... Bathtub temperature sensor 25 ... Boil-up temperature setting means 26 ... Boil-up time setting means 27 ... Operating time measurement means 29 ... Heating time calculation means 30 ... Comparison means 31 ... Heating selection means 32 ... Continuous operation time calculation means 33 ... Second comparison means 34 ... Second 2 heating selection means 35 ... third comparison means 36 ... heating time difference calculation means 37 ... auxiliary heating time calculation means 38 ... auxiliary heating combined use control means

Claims

A hot water storage tank that stores hot water in a state where a temperature stratification is formed by attaching a circulation pipe that is taken out from the lower part and supplied from the upper part,
Heating means provided in the circulation pipe for heating water taken out from the hot water storage tank;
A circulation pump which is provided in the circulation pipe and takes out water from the hot water storage tank and supplies hot water after heating to the hot water storage tank;
Hot water filling means connected to the hot water storage tank and supplying hot water in the hot water storage tank into the bathtub;
A branch pipe for circulation that is connected to the circulation pipe in parallel with the hot water storage tank and takes out the hot water that has passed through the heating means;
In the cogeneration system provided with the heat exchanger for reheating which is provided in the branch piping for circulation and circulates and heats the hot water in the bathtub in response to the reheating signal,
The heating means comprises exhaust heat heating means using the exhaust heat of the combined heat and power supply device as a heat source, and auxiliary heating means using a dedicated heat source having a high heating capacity,
A bathtub temperature sensor for measuring the temperature of hot water in the bathtub;
Boiling temperature setting means for setting the boiling temperature of hot water in the bathtub;
Responding to the reheating signal, heating by the exhaust heat heating means based on the temperature of the hot water in the bathtub measured by the bathtub temperature sensor and the boiling temperature set by the boiling temperature setting means Heating time calculating means for calculating the heating time required to reach the boiling temperature when
Comparing the required heating time calculated by the heating time calculating means with the exhaust heat continuous operation time sufficient to make use of the characteristics of the combined heat and power supply device, the exhaust heat is exhausted when the required heating time is longer than the exhaust heat continuous operation time. Comparison means for outputting a heating signal and outputting an auxiliary heating signal when it is short,
A heating selection means for automatically switching to a state in which the exhaust heat heating means is activated in response to the exhaust heat heating signal from the comparison means and to a state in which the auxiliary heating means is activated in response to the auxiliary heating signal; Cogeneration system characterized by having

A hot water storage tank that stores hot water in a state where a temperature stratification is formed by attaching a circulation pipe that is taken out from the lower part and supplied from the upper part,
Heating means provided in the circulation pipe for heating water taken out from the hot water storage tank;
A circulation pump which is provided in the circulation pipe and takes out water from the hot water storage tank and supplies hot water after heating to the hot water storage tank;
Hot water filling means connected to the hot water storage tank and supplying hot water in the hot water storage tank into the bathtub;
A branch pipe for circulation that is connected to the circulation pipe in parallel with the hot water storage tank and takes out the hot water that has passed through the heating means;
In the cogeneration system provided with the heat exchanger for reheating which is provided in the branch piping for circulation and circulates and heats the hot water in the bathtub in response to the reheating signal,
The heating means comprises exhaust heat heating means using the exhaust heat of the combined heat and power supply device as a heat source, and auxiliary heating means using a dedicated heat source having a high heating capacity,
A bathtub temperature sensor for measuring the temperature of hot water in the bathtub;
Boiling temperature setting means for setting the boiling temperature of hot water in the bathtub;
Responding to the reheating signal, heating by the exhaust heat heating means based on the temperature of the hot water in the bathtub measured by the bathtub temperature sensor and the boiling temperature set by the boiling temperature setting means Heating time calculating means for calculating the heating time required to reach the boiling temperature when
An operation time measuring means for measuring a continuous operation time of the cogeneration apparatus;
In response to the follow-up signal, when the combined heat and power device is in an operating state, the required heating time calculated by the heating time calculating means and the continuous operation time measured by the operating time measuring means are added. Continuous operation time calculating means for calculating continuous operation time;
When the continuous operation time calculated by the continuous operation time calculation means is compared with the exhaust heat continuous operation time, and when the continuous operation time is longer than the exhaust heat continuous operation time, the exhaust heat heating signal is output and short Second comparison means for outputting an auxiliary heating signal;
A first switch that automatically activates the exhaust heat heating means in response to the exhaust heat heating signal from the second comparison means and activates the auxiliary heating means in response to the auxiliary heating signal; A cogeneration system comprising two heating selection means.

A hot water storage tank that stores hot water in a state where a temperature stratification is formed by attaching a circulation pipe that is taken out from the lower part and supplied from the upper part,
Heating means provided in the circulation pipe for heating water taken out from the hot water storage tank;
A circulation pump which is provided in the circulation pipe and takes out water from the hot water storage tank and supplies hot water after heating to the hot water storage tank;
Hot water filling means connected to the hot water storage tank and supplying hot water in the hot water storage tank into the bathtub;
A branch pipe for circulation that is connected to the circulation pipe in parallel with the hot water storage tank and takes out the hot water that has passed through the heating means;
In the cogeneration system provided with the heat exchanger for reheating which is provided in the branch piping for circulation and circulates and heats the hot water in the bathtub in response to the reheating signal,
The heating means comprises exhaust heat heating means using the exhaust heat of the combined heat and power supply device as a heat source, and auxiliary heating means using a dedicated heat source having a high heating capacity,
A bathtub temperature sensor for measuring the temperature of hot water in the bathtub;
Boiling temperature setting means for setting the boiling temperature of hot water in the bathtub;
Responding to the reheating signal, heating by the exhaust heat heating means based on the temperature of the hot water in the bathtub measured by the bathtub temperature sensor and the boiling temperature set by the boiling temperature setting means Heating time calculating means for calculating the heating time required to reach the boiling temperature when
Boil-up time setting means for setting the boil-up time;
In response to the reheating signal, the boiling time set by the boiling time setting means is compared with the exhaust heat continuous operation time, and when the boiling time is longer than the exhaust heat continuous operation time, the boiling time is set. Third comparing means for outputting;
The heating for calculating the difference in heating time when the required heating time is longer than the boiling time by comparing the boiling time output from the third comparing means with the required heating time calculated by the heating time calculating means. A time difference calculating means;
Auxiliary heating time calculating means for calculating an auxiliary heating time sufficient to obtain the heating amount of the heating time difference calculated by the heating time difference calculating means by the auxiliary heating means;
A cogeneration system comprising: auxiliary heating combined control means for automatically switching to a state in which the auxiliary heating means is activated in combination with the exhaust heat heating means for the auxiliary heating time calculated by the auxiliary heating time calculating means.